Flexible Multi-Panel Sterilization Assembly

ABSTRACT

A multi-panel sterilization assembly includes a barrier panel formed of a permeable material, a fold protection panel, and at least one panel attachment means. The barrier panel has a first end, an opposed second end, and a midpoint delineating the barrier panel into a content receiving region and a content covering region. Panel attachment means are located at or near edges of the barrier panel to identify the content receiving region. The fold protection panel has a proximal end and an opposed distal end. After the barrier panel is folded at or near the midpoint to bring its second end near its first end and its edges are brought together and secured by the panel attachment means to form a package, the fold protection panel folds at or near a pre-determined fold line to cover at least a portion of the edges of the folded barrier panel.

This application is a continuation of U.S. Ser. No. 12/850,697 entitled“Flexible Multi-Panel Sterilization Assembly” by Melissa R. Gaynor etal., filed Aug. 5, 2010, which is hereby incorporated by referenceherein for all purposes.

FIELD OF THE INVENTION

The present invention relates in general to disposable wraps used tocontain content to be sterilized and store that content asepticallyuntil use.

BACKGROUND OF THE INVENTION

A variety of products such as gowns, sheets, drapes, instruments, etc.which are required during surgery or other aseptic procedures, are usedon a daily basis in the normal operation of hospitals, clinics and thelike. Where such products are not pre-packaged in a sterile state, it isnecessary for the hospital or clinic to sterilize them before use.Furthermore, where these products are not disposable, and are employedmore than once, it is necessary that they be cleaned and otherwiseprepared for subsequent use. Prior to such use, however, it is essentialthat such products be sterilized.

Due to the volume of materials involved, it is often necessary tosterilize and store these products for later use. Accordingly, there hasbeen developed a procedure where such products, after cleaning,laundering and the like, are wrapped in sterilization fabric and thensterilized and stored for subsequent use. Disposable sterilizationfabric is typically cut into predetermined rectangular shapes and soldas sterilization wraps.

Traditional wrapping of a sterilization tray or similar articles in aconventional disposable sterilization wrap often involves a large amountof redundant material as excess corners and overlapping plies aregathered, folded, and secured together at the top of the sterilizationtray.

Conventional disposable sterilization wrap is a flat, featureless sheetof material that may occasionally contain one or more additional layersof material for strength or absorbency. This flat, featurelessconfiguration provides no information or guidance to a person wrappingan article with the flat sheet of material on how to wrap an article.

Conventional disposable sterilization wrap is frequently made ofinexpensive, relatively impermeable material such as, for example, paperand the like. The properties of these materials have generallyinfluenced folding techniques and wrapping configurations to ensure thesterility of the wrapped tray or article.

For example, U.S. Pat. No. 5,635,134 to Bourne, et al. discloses amulti-ply sterilization wrap which is formed by joining one or moresheets of sterilization wrap (e.g., two separate sheets or one sheetfolded over) together to form two similarly sized, superposed panelsthat allow convenient dual wrapping of an article. As another example,U.S. Patent Application Publication No. 2001/0036519 by Robert T. Bayerdiscloses a two ply sterilization wrap that is formed of a single sheetof sterilization wrap material which is folded to form two similarlysized, superposed panels that are bonded to each other. As yet anotherexample, U.S. Patent Application Publication No. 2005/0163654 byStecklein, et al. discloses a sterilization wrap material that has afirst main panel and a second panel that is smaller than the main panel.The second panel is superposed and bonded to the central portion of themain panel such that it is contained entirely within the main panel toreinforce the main panel and/or provide additional absorbency.

Generally speaking, in these and other examples, large sheets ofconventional disposable sterilization wrap are typically used to createlarge expanses of overlapping materials using one or two standard foldtechniques. Large amounts of materials and multiple folds are used tocreate a tortuous path (e.g., at least two sharp turns in the samedirection) to inhibit passage of airborne bacteria past the edges of thesterilization wrap past the folds in response to changes in air pressurein the volume enclosed by the sterilization wrap. That is, large amountsof material and multiple folds are a conventional technique used toaddress a “bellows effect” from handling or dropping of wrapped contentsthat may cause rapid volume and pressure changes that force air out ofand back into the wrapped package past the edges and folds ofsterilization wrap enclosing the content that has been sterilized. Theprinciple of employing a tortuous path to maintain sterile conditions issometimes referred to as Louis Pasteur's tortuous path principle ortheory.

These conventional techniques and the resulting fold configurationsrequire manipulating excess amount of materials during the wrapping andunwrapping process. It takes experience and a certain level of skill towrap a tray or similar article quickly and reliably. Because ofscheduling and cost pressures, medical equipment needed for someprocedures may require immediate turnaround and must be processed,sterilized and available for use within hours of its use in a previousprocedure. As turnaround times continue to compress, there is acorresponding increase in the need to wrap an article even more quicklywhile ensuring the integrity of the wrapping.

Errors during the wrapping of an article prior to sterilization orduring the unwrapping of a sterilized article in the operating room haveimportant financial and time consequences. Improperly wrapped packagesare more likely to become compromised by aggressive handling orexcessive amounts of routine handling. A contaminated article requiringre-sterilization can delay a critical medical procedure. A typicalhospital may spend approximately fifty-thousand dollars ($50,000.00 US)annually on sterilization wrap, sterilization pouches or sterilizationcontainers. Failure of the sterilization wrap, pouch or container,and/or errors related to wrapping or unwrapping will requirere-sterilization of the contents if another sterilized substitute is notimmediately available. If there is any doubt about the sterility of anyitem, it must be re-sterilized. Depending on the procedure, it may costup to eight-thousand dollars ($8,000.00) to reschedule a single medicalprocedure. Thus, the cost of only a few negative events may add up to asignificant portion of what is spent on sterilization wraps, pouches, orcontainers.

There are many ways items conventionally wrapped or packaged insterilization wraps can be contaminated. For example, soil, moisture,and bacteria can be forced into the package by incorrect or excessivehandling, poor storage facilities, or improper techniques. As notedabove, an aerosol or bellows effect always occurs, to some extent, bythe squeezing action of the hands each time the package is handled.Dropping a package onto a hard surface such as a floor can also create abellows effect by rapidly compressing the volume of the package whichthen recovers some or all of its volume and/or which may allow bacteriato enter the package through ruptured seals or small breaks or tears ofthe material that are not easily detected. Incorrect opening of thepackage may compromise the sterility of the contents of the package.

Certain modes of wrap failure such as knife cuts, abrasion and puncturesare well-recognized. There are other modes of failure that are as commonif not more common. These include pressure cuts, snag cuts and pressureholes.

A pressure cut can appear as a knife cut, but upon closer examination,the fibers around the very edge of the cut have been “welded” or stucktogether. The edge of the cut may feel hard to the touch. This type ofcut usually follows the perimeter or outline of the bottom of theinstrument tray. It may also occur on the top of the instrument tray, ifa number of trays have been stacked upon one another. An example of atypical event that may generate a pressure cut would be lifting thefront end of a 20 pound tray so that all the weight of the tray isresting on a back edge, and pulling it across the storage shelf beforelifting. This is similar to cutting the wrap with scissors; the materialis caught between two layers of hard solid interfaces with a shearingaction applied to the material.

In a snag cut, the edges of the cut show loose fibers hanging and/orthere are individual fibers spanning across the width of the cut. Theedges of the cut are not rough or hard, as with the pressure cut. Inlarger snag cuts, the shape of the cut area resembles a triangle, withthe point of the triangle being where the snag began. The snag cut willoccur along the edges of the wrapped instrument tray if the tray is veryloosely wrapped. Otherwise, this type of cut will occur on the otherareas of the tray where the wrap is too loose and can be caught by roughsurfaces or corners. This type of cut is generally due to the tray beingpulled or dragged across a roughened surface, often an older, well-usedsterilizer cart. This cut can also occur when a loosely wrapped area ofa tray gets caught on the corners or edges of objects.

A pressure hole may appear to be a tiny opening where the fibers aroundthe very edge of the hole have been “welded” or stuck together. Thistype of hole is usually found along the perimeter of the bottom of aninstrument tray. It may also occur on the top of the instrument tray ifa number of trays have been stacked upon it. An example of a typicalevent that may generate a pressure hole would be a tray being dropped(even a small distance) onto an edge of a cart or storage shelf whilebeing transported to different areas of the hospital.

The use of large sheets of conventional disposable sterilization wrapwith standard fold techniques provides large expanses of overlappingmaterials and multiple folds that are also generally thought to helpprotect against pressure cuts, snag cuts and pressure holes as well asthe more commonly recognized modes of failure (i.e., knife cuts,abrasion and punctures). Accordingly, conventional solutions employlarger sheets of material, greater numbers of layers of material,combinations of large sheets of different materials, centrally locatedreinforcing or absorbent zones, bumpers or pads that are attached to thecorners of trays, and combinations thereof—all of which require usingand manipulating excessive amounts of material during the wrapping andunwrapping process, adding difficulty that slows the wrapping andunwrapping process, and creating waste.

Accordingly, there is an unmet need for an easy to use assembly, packageor system that simplifies the task of wrapping or preparing an articlefor sterilization. There is also an unmet need for an easy to usepackage or system that simplifies the task of unwrapping a sterilizedarticle. In addition to these needs, there is also a need for anarrangement, assembly or system of sterilization fabric that reduces oreliminates failures or breaches that compromises the sterility of thecontents enclosed by the same. That is, a need exists for an assembly orsystem of sterilization wrap or fabric that reduces the occurrence ofpressure cuts, pressure holes, snag cuts and the like while stillreducing the amount of sterilization fabric needed for sterileprocessing of an instrument tray as well as reducing the complexity,difficulty and/or time required to wrap or cover the instrument tray.There is also an unmet need to reduce the amount of sterilization fabricneeded for the sterile processing of an instrument tray.

BRIEF SUMMARY OF THE INVENTION

The problems described above are addressed by the present inventionwhich encompasses a disposable flexible multi-panel sterilizationassembly. The disposable flexible multi-panel sterilization assemblyincludes a barrier panel composed of a permeable sheet material havingbarrier properties, panel attachment means for securing the barrierpanel into a package; and a fold protection panel. The barrier panelincludes: a first surface and a second opposing surface; a first endgenerally defining a pre-determined fold line; a second end opposite thefirst end; a first edge that is generally perpendicular to thepre-determined fold line; a second edge that is generally opposite thepre-determined fold line; and a third edge that is generallyperpendicular to the pre-determined fold line. Desirably, the barrierpanel may have a fourth edge that is located generally opposite thepre-determined fold line such that the second edge and the fourth edgeform an apex or vertex. More desirably, the barrier panel may have afourth edge and a fifth edge to define a non-square or non-rectangularshape such that, for example, the fourth edge and a fifth edge generallyconverge toward the second edge such that the second end of the barrierpanel is narrower than the first end of the barrier panel.

The barrier panel may have a width that is the distance from the firstedge to the third edge and a length that is the distance from the firstend to the second end. According to an aspect of the invention, thebarrier panel has a midpoint along the length which spans or runsbetween the first edge and the third edge to generally delineate thebarrier panel into a content receiving region extending from thepre-determined fold line to the midpoint and a content covering regionextending from the midpoint to the second edge. According to an aspectof the invention, the surface area of the content receiving region maybe from about 25 percent to about 49 percent of the total surface areaof the barrier panel. For example, the surface area of the contentreceiving region may be from about 35 percent to about 45 percent of thetotal surface area of the barrier panel.

The multi-panel sterilization assembly includes a panel attachment meanslocated between the pre-determined fold line and the midpoint of thebarrier panel. The panel attachment means is desirably at or near thefirst edge or the third edge of the barrier panel. Desirably, the panelattachment means may be at or near both the first edge and the thirdedge of the barrier panel and may be used to attach the barrier panel toitself after the barrier panel is folded around content to be sterilizedto form a package. In an aspect of the invention, the panel attachmentmeans may be located in close proximity to the first edge and the thirdedge of the barrier panel and/or may extend from the first edge and thethird edge of the barrier panel. The panel attachment means may beadhesive tape, double-sided adhesive tape, cleavable release tapes,layered release tapes, cohesive materials, hook and loop fasteningsystems, mechanical fastening systems including, but not limited to,snaps, clips, magnets, catches, slots and tabs, and combinationsthereof. According to an aspect of the invention, the panel attachmentmeans is joined to the barrier panel at a pre-determined position. Thispre-determined position may near the pre-determined fold line. The panelattachment means may be configured to identify the barrier panel'scontent receiving region and further to join the barrier panel's firstedge and third edge to each other or to a portion of the contentcovering region after the barrier panel has been folded at or near itsmidpoint such that its second end is brought near its first end.

The multi-panel sterilization assembly further includes a foldprotection panel in juxtaposed communication with the barrier panel.That is, the fold protection panel desirably extends from the barrierpanel. If the fold protection panel is a separate piece of material, itis desirably immediately adjacent the barrier panel in side-by-siderelationship. The fold protection panel includes: a proximal endgenerally adjacent or adjoining the pre-determined fold line; a distalend generally opposite the proximal end; and at least a first edge and asecond edge extending from the proximal end to the distal end. Accordingto the present invention, the fold protection panel may have at least athird edge located at or along its distal end. The fold protection panelmay be configured so it has barrier properties. For example, the foldprotection panel may be formed of the same material as the barrierpanel. As another example, the fold protection panel may be formed ofthe same piece of material as the barrier panel.

In an aspect of the invention, the fold protection panel desirably has awidth that is the distance from the first edge to the second edge and alength that is the distance from the proximal end to the distal end,such that, after the barrier panel has been folded at or near thebarrier panel's midpoint, the barrier panel's second end is brought nearits first end and its first and third edges are joined to each other orto its content covering region to form a package, the fold protectionpanel is configured to fold at or near the pre-determined fold line tocover at least the first edge and the third edge of the folded barrierpanel.

According to the present invention, the barrier panel may be composed ofat least one layer of a breathable nonwoven material. Desirably, thebreathable nonwoven material is a laminate composed of a layer ofspunbonded filaments, a layer of meltblown fibers, and a layer ofspunbonded filaments. The permeability of the barrier panel may rangefrom 25 to about 500 cubic feet per minute (CFM) as characterized interms of Frazier permeability. For example, the permeability of thebarrier panel may range from 25 to about 400 cubic feet per minute. Asyet another example, the permeability of the barrier panel may rangefrom 25 to about 300 cubic feet per minute.

The sterilization assembly further includes at least one pull tab. Thepull tab may be unitary with the barrier panel or it may be attached tothe second end of the barrier panel. The pull tab may be formed of thesame material as the barrier panel or may be formed of one or moredifferent materials. The pull tab provides a feature that allows a userto unwrap a sterilized article aseptically. That is, a person unwrappingan article that is folded in the flexible multi-panel sterilizationassembly may use the pull tab to avoid reaching over the sterile fieldgenerally presented from unwrapping and spreading out the sterilecontent-contacting surface of the barrier panel.

The sterilization assembly may further include one or more discretereinforcement elements. These elements are desirably in the contentreceiving region that define an area for receiving content to besterilized. The reinforcement element(s) may include one or more layersof materials selected from fibrous webs, impermeable films, permeable orporous films, apertured films, foams, foils and combinations thereof.

According to an aspect of the invention, the sterilization assembly mayfurther include indicia or instructions on the sterilization assemblyitself to inform the proper folding of the assembly into a package.

In an aspect of the invention, there is provided a disposable flexiblemulti-panel sterilization assembly that includes a barrier panel formedfrom a sheet of barrier material (e.g., barrier fabric) having at leastone panel edge. The barrier panel is configured to be folded aroundcontent to be sterilized to form a package. Barrier panel attachmentmeans are located on a portion of the barrier panel for securing one ormore panel edges of the barrier panel in a folded configuration aroundcontent to be sterilized. The barrier panel attachment means areconfigured to secure the one or more panel edges in a foldedconfiguration with substantially greater resistance to shear force thanto peel force. The multi-panel sterilization assembly further includes afold protection panel extending from the barrier panel. The foldprotection panel includes a proximal end generally adjacent the barrierpanel and a distal end generally opposite the proximal end such that thedistal end of the fold protection panel covers the one or more paneledges of the barrier panel after the barrier panel is in the foldedconfiguration.

The barrier panel attachment means are used to attach the barrier panelto itself after the barrier panel is folded around content to besterilized to form a package. The barrier panel attachment means may beadhesive tape, double-sided adhesive tape, cleavable release tapes,cohesive materials, hook and loop fastening systems, mechanicalfastening systems including, but not limited to, snaps, clips, magnets,catches, slots and tabs, and combinations thereof.

Yet another aspect of the invention relates to a disposable flexiblemulti-panel sterilization assembly that includes a barrier panel formedfrom a sheet of barrier material (e.g., barrier fabric) having at leastone panel edge. The barrier panel is configured to be folded aroundcontent to be sterilized to form a package. Barrier panel attachmentmeans are located on a portion of the barrier panel for securing one ormore panel edges of the barrier panel in a folded configuration aroundcontent to be sterilized. The barrier panel attachment means areconfigured to secure the one or more panel edges in a foldedconfiguration. The multi-panel sterilization assembly further includes afold protection panel extending from the barrier panel. The foldprotection panel includes a proximal end generally adjacent the barrierpanel and a distal end generally opposite the proximal end such that thedistal end of the fold protection panel covers the one or more paneledges of the barrier panel after the barrier panel is in the foldedconfiguration and so less than ten (10) stacked plies of material arepresent as a result of the folding of the sterilization assembly aroundan article. Desirably, less than five (5) stacked plies of material arepresent as a result of folding of the sterilization assembly around anarticle such as a sterilization tray.

Another embodiment of the present invention encompasses a multi-panelsterilization assembly having a barrier panel composed of a permeablesheet material providing barrier properties. The barrier panel includes:a first surface and a second opposing surface; a first end generallydefining a pre-determined fold line; a second end opposite the firstend; a first edge that is generally perpendicular to the pre-determinedfold line; a second edge that is generally parallel to thepre-determined fold line; a third edge that is generally perpendicularto the pre-determined fold line; a fourth edge located between thesecond edge and the third edge; and, a fifth edge located between thefirst edge and the second edge. The barrier panel has a first width thatis the distance from the first edge to the third edge and second widththat is the distance from the fourth edge to the fifth edge; a lengththat is the distance from the first end to the second end, the barrierpanel having a midpoint along the length and extending between the firstedge and the third edge or the fourth edge and the fifth edge togenerally delineate the barrier panel into a content receiving regionextending from the pre-determined fold line to the midpoint and acontent covering region extending from the midpoint to the second edge.

The multi-panel sterilization assembly includes at least one pull tab atthe second end of the barrier panel; a panel attachment means betweenthe pre-determined fold line and the midpoint of the barrier panel andat or near the first edge or the third edge; the panel attachment meansbeing joined to the barrier panel at a pre-determined position toidentify the barrier panel's content receiving region and further tojoin the barrier panel's first edge and third edge to each other or to aportion of the content covering region after the barrier panel has beenfolded at or near its midpoint such that its second edge is brought nearits first end.

The multi-panel sterilization assembly further includes a foldprotection panel in juxtaposed communication with the barrier panel. Thefold protection panel includes: a proximal end generally adjacent oradjoining the pre-determined fold line; a distal end generally oppositethe proximal end; and at least a first edge and a second edge extendingfrom the proximal end to the distal end, the fold protection panelhaving a width that is the distance from the first edge to the secondedge and a length that is the distance from the proximal end to thedistal end, such that, after the barrier panel has been folded at ornear its midpoint so its second end is brought near its first end andits first and third edges are joined to each other or to its contentcovering region to form a package, the fold protection panel isconfigured to fold at or near the pre-determined fold line to cover atleast the first edge and the third edge of the folded barrier panel.

These and other features and advantages of the invention will becomemore apparent to one skilled in the art from the following descriptionand claims when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood by reading the DetailedDescription of the Invention with reference to the accompanying drawingfigures, in which like reference numerals denote similar structure andrefer to like elements throughout, and in which:

FIG. 1 is an illustration of an exemplary prior art sterilization wrapsystem.

FIG. 2 is an illustration of an exemplary prior art sterilization wrapsystem.

FIG. 3 is an illustration of an exemplary prior art sterilization wrapsystem.

FIGS. 4A to 4E are illustrations of an exemplary sequence of folding anexemplary prior art sterilization wrap system using a conventionalenvelope fold.

FIGS. 5A to 5E are illustrations of an exemplary sequence of folding anexemplary prior art sterilization wrap system using a conventionalsquare fold.

FIG. 6 is an illustration of an exemplary disposable flexiblemulti-panel sterilization assembly.

FIG. 7A is an illustration of an exemplary disposable flexiblemulti-panel sterilization assembly.

FIG. 7B is an illustration of an exemplary disposable flexiblemulti-panel sterilization assembly with an integral pull tab.

FIG. 7C is an illustration highlighting a detail of the exemplarydisposable flexible multi-panel sterilization assembly of FIG. 7B.

FIG. 8A is an illustration of an exemplary disposable flexiblemulti-panel sterilization assembly.

FIG. 8B is an illustration showing the opposite side of the exemplarydisposable flexible multi-panel sterilization assembly of FIG. 8A.

FIGS. 9A to 9E are illustrations of an exemplary sequence of folding anexemplary disposable flexible multi-panel sterilization assembly.

FIGS. 10A to 10D are illustrations of exemplary disposable flexiblemulti-panel sterilization assemblies showing exemplary reinforcingelements.

FIGS. 11A to 11B are illustrations of exemplary reinforcing elements.

FIG. 12 is an illustration of an exploded or broken apart perspectiveview of exemplary features of an exemplary disposable flexiblemulti-panel sterilization assembly.

FIG. 13 is an illustration of an exploded or broken apart cross-sectionview of exemplary features of an exemplary disposable flexiblemulti-panel sterilization assembly.

FIG. 14 is an illustration of an article positioned on conventionalsterilization wrap in preparation for simultaneously wrapping bothpanels using a conventional envelope fold.

FIG. 15 is an illustration of an article wrapped with conventionalsterilization wrap using a conventional envelope fold.

FIG. 16 is an illustration an article positioned on two superposed butnon-aligned sheets of conventional sterilization wrap in preparation forwrapping each panel sequentially using a conventional envelope fold.

FIG. 17 is an illustration of the article of FIG. 16 wrapped with onesheet of conventional sterilization wrap and positioned on the remainingsheet of conventional sterilization wrap in preparation for subsequentwrapping.

FIG. 18 is an illustration of the completion of the second wrapping ofthe article of FIG. 16 with the remaining sheet of conventionalsterilization wrap of FIG. 17.

FIG. 19 is an illustration that identifies regions of a package formedby wrapping an article wrapped with conventional sterilization wrap.

FIG. 20 is an illustration showing the regions of FIG. 19 sectioned ordivided into respective arrays.

FIG. 21 is an illustration is an article positioned on an exemplarymulti-panel sterilization assembly.

FIG. 22 is an illustration is an article positioned on another exemplarymulti-panel sterilization assembly.

FIG. 23 is an illustration showing the regions of FIG. 24 into sectionedor divided into respective arrays.

FIG. 24 is an illustration the article of FIG. 21 or FIG. 22 thatidentifies regions of a package formed by wrapping an article using anexemplary multi-panel sterilization assembly.

FIG. 25 is an illustration showing separated regions of a wrappedarticle according to FIG. 20 or 23, their respective sectioned arrays,and location of specimens within the arrays.

FIG. 26 is an illustration of a graph of data and information from Table5.

FIG. 27 is an illustration of another graph of data and information fromTable 5.

FIG. 28 is an illustration of a graph of data and information from Table6.

FIG. 29 is an illustration of another graph of data and information fromTable 6.

FIG. 30 is an illustration of a graph of data and information from Table7.

FIG. 31 is an illustration of a graph of data and information from Table8.

FIG. 32 is an illustration of a graph of data and information from Table9.

FIG. 33 is an illustration of a graph of data and information from Table10.

FIG. 34 is an illustration of a graph of data and information from Table11.

FIG. 35 is an illustration of a graph of data and information from Table12.

FIG. 36 is an illustration of a graph of data and information from Table13.

FIG. 37 is an illustration of a graph of data and information from Table14.

FIG. 38 is an illustration of a graph of data and information from Table15.

FIG. 39 is an illustration of a graph of data and information from Table16.

FIG. 40 is an illustration of a graph of data and information from Table17.

FIG. 41 is an illustration of a graph of data and information from Table18.

FIG. 42 is an illustration of a graph of data and information from Table19.

DEFINITIONS

As used herein, the term “disposable” refers to a product that is soinexpensive that it may economically be discarded after only a singleuse. Products that are “disposable” are typically intended for singleuse. The term “single-use” refers to a product that is intended to beused for only once and is not intended to be re-used, re-conditioned,restored or repaired after that use. These products offer advantages inclinical settings by reducing the potential for contamination orinfection. In addition, these products can enhance work flow since theyare not collected and assembled for reprocessing and reuse.

As used herein, the term “sterilization assembly” refers to a flexiblearticle composed of fabric(s) and/or flexible material(s) that iswrapped around, folded around or otherwise encloses a non-sterilearticle or non-sterile content prior to sterilization. A sterilizationassembly has multiple panels and/or sections providing specific physicalproperties, functional characteristics and/or structure that provideadvantages for wrapping or folding, handling, strength, sterilization,storage after sterilization, and/or unwrapping or unfolding.

As used herein, the term “nonwoven web” refers to a web that has astructure of individual fibers or filaments which are interlaid, but notin an identifiable repeating manner. Nonwoven webs have been, in thepast, formed by a variety of processes known to those skilled in the artsuch as, for example, meltblowing, spunbonding and bonded carded webprocesses.

As used herein, the term “spunbonded web” refers to a web of smalldiameter fibers and/or filaments which are formed by extruding a moltenthermoplastic material as filaments from a plurality of fine, usuallycircular, capillaries in a spinnerette with the diameter of the extrudedfilaments then being rapidly reduced, for example, by non-eductive oreductive fluid-drawing or other well known spunbonding mechanisms. Theproduction of spunbonded nonwoven webs is illustrated in patents such asAppel, et al., U.S. Pat. No. 4,340,563; Dorschner et al., U.S. Pat. No.3,692,618; Kinney, U.S. Pat. Nos. 3,338,992 and 3,341,394; Levy, U.S.Pat. No. 3,276,944; Peterson, U.S. Pat. No. 3,502,538; Hartman, U.S.Pat. No. 3,502,763; Dobo et al., U.S. Pat. No. 3,542,615; and Harmon,Canadian Patent No. 803,714.

As used herein, the term “meltblown fibers” means fibers formed byextruding a molten thermoplastic material through a plurality of fine,usually circular, die capillaries as molten threads or filaments into ahigh-velocity gas (e.g. air) stream which attenuates the filaments ofmolten thermoplastic material to reduce their diameters, which may be tomicrofiber diameter. Thereafter, the meltblown fibers are carried by thehigh-velocity gas stream and are deposited on a collecting surface toform a web of randomly disbursed meltblown fibers. The meltblown processis well-known and is described in various patents and publications,including NRL Report 4364, “Manufacture of Super-Fine Organic Fibers” byV. A. Wendt, E. L. Boone, and C. D. Fluharty; NRL Report 5265, “AnImproved device for the Formation of Super-Fine Thermoplastic Fibers” byK. D. Lawrence, R. T. Lukas, and J. A. Young; and U.S. Pat. No.3,849,241, issued Nov. 19, 1974, to Buntin, et al.

As used herein, “ultrasonic bonding” means a process performed, forexample, by passing the fabric between a sonic horn and anvil roll asillustrated in U.S. Pat. No. 4,374,888 to Bornslaeger, the entirecontents of which is incorporated herein by reference.

As used herein “point bonding” means bonding one or more layers offabric at a plurality of discrete bond points. For example, thermalpoint bonding generally involves passing a fabric or web of fibers to bebonded between a heated roll assembly such as, for example, a heatedcalender roll and an anvil roll. The calender roll is usually patternedin some way so that the entire fabric is not bonded across its entiresurface, and the anvil roll is usually smooth. As a result, variouspatterns for calender rolls have been developed for functional and/oraesthetic reasons. One example of a pattern has points and is the HansenPennings or “H&P” pattern with about a 30% bond area with about 200bonds/square inch (31 bonds/square cm) as taught in U.S. Pat. No.3,855,046 to Hansen and Pennings. Another example is shown in U.S.Design Pat. No. 239,566 to Vogt. Typically, the percent bonding areavaries from around 5% to around 30% of the area of the fabric laminateweb. Spot bonding holds the laminate layers together as well as impartsintegrity to each individual layer by bonding filaments and/or fiberswithin each layer without destroying the breathability or hand of thefabric.

DETAILED DESCRIPTION OF INVENTION

In describing the various embodiments of the present invention, asillustrated in the figures and/or described herein, specific terminologyis employed for the sake of clarity. The invention, however, is notintended to be limited to the specific terminology so selected, and itis to be understood that each specific element includes all technicalequivalents that operate in a similar manner to accomplish similarfunctions.

Referring now to FIG. 1, there is shown an exemplary conventionaldisposable sterilization wrap 10 having a multiple-ply configurationwhich is formed by joining one or more sheets 12 of sterilization wraptogether to form two similarly sized, superposed panels 14 and 16 thatallow convenient dual wrapping of an article. While one sheet may befolded back on itself to provide the multiple-ply configuration, twoseparate sheets are more typically used.

FIG. 2 is an illustration of an exemplary conventional disposablesterilization wrap 20 as generally disclosed in U.S. Patent ApplicationPublication No. 2001/0036519 by Robert T. Bayer. The conventionaldisposable sterilization wrap 20 is a two ply sterilization wrap formedof a single sheet 22 of sterilization wrap material which is folded toform two similarly sized, superposed panels 24 and 26 that are bonded toeach other.

FIG. 3 is an illustration of yet another example of a conventionaldisposable sterilization wrap 30 as generally disclosed in U.S. PatentApplication Publication No. 2005/0163654 by Stecklein, et al. Theconventional disposable sterilization wrap 30 has a first main panel 32and a second panel 34 that is much smaller than the main panel 32. Thesecond panel 34 is superposed and bonded to the central portion 36 ofthe main panel 32 to reinforce the main panel 32 and/or provideadditional absorbency.

Generally speaking, in these and other examples, large sheets ofconventional disposable sterilization wrap are typically used to createlarge expanses of overlapping materials using one or two standard foldtechniques. These standard techniques and the resulting foldconfigurations require manipulating excess amount of materials duringthe wrapping and unwrapping process. It takes experience and a minimumlevel of skill to reliably wrap a tray or similar article quickly.

FIGS. 4A through 4E illustrate an exemplary sequence of steps inwrapping an article utilizing a conventional sterilization wrap. Asillustrated in FIG. 4A, a square or generally rectangular wrap 40 isspread out flat and an article 42 to be wrapped is placed in a centralregion 44 of the wrap 40 in a generally diagonal relationship to theorientation of the wrap 40 in a pattern conventionally referred to as anenvelope fold. Referring to FIG. 4B, a first end 46 of the wrap isfolded up at the base of the article 42 and brought over the article 42.Generally speaking, the sterilization wrap must be sufficiently large inarea to provide enough material to substantially cover the article inthe initial fold. The first folded end 46 is back-folded to create asmall tail 48. This sequence is generally repeated for the remainingsecond end 50 and the third end 52. Again, the sterilization wrap mustbe sufficiently sized in area to provide enough material for the secondend 50 and the third end 52 to substantially overlap such that theentire or substantially the entire second end 50 is covered by the thirdend 52. The fourth end 54 is folded over and taped to form a wrappedpackage.

FIGS. 5A through 5E illustrate an exemplary sequence of steps inwrapping an article utilizing a conventional sterilization wrap. Asillustrated in FIG. 5A, a square or generally rectangular wrap 60 isspread out flat and an article 62 to be wrapped is placed in a centralregion 64 of the wrap 60 in a generally parallel relationship to theorientation of the wrap 60 in a pattern conventionally referred to as asquare fold. Referring to FIG. 5B, a bottom end 66 of the wrap is foldedup at the base of the article 62 and brought over the article 62.Generally speaking, the sterilization wrap must be sufficiently large inarea to provide enough material to substantially cover the article inthe initial fold. The folded bottom end 66 is back-folded to create asmall tail 68. This sequence is generally repeated for the remaining topend 70 and the left side end 72. Again, the sterilization wrap must besufficiently sized in area to provide enough material for the top end 70and the left side end 72 to substantially overlap such that the entireor substantially the entire bottom end 70 is covered by the left sideend 72. The right side end 74 is folded over and taped 76 to form awrapped package.

A typical sterilization tray with the dimensions of 10 inches (25.4 cm)by 20 inches (50.8 cm) by 5 inches tall (12.7 cm) typically requires asquare piece of sterilization fabric having each side measuring 45inches for wrapping and sterile processing. This large size piece isneeded so that the corner of the fabric can be folded all the way acrossthe top of the tray with some additional excess material so that thepreparer of the tray feels confident that the contents are covered andthat the piece of fabric will stay down and not spring back. Using a 45inch square piece of fabric means that 2025 square inches of material(approximately 13,064 square centimeters) is being used to enclose atray with a surface area of just 700 square inches (approximately 4,516square centimeters). In other words, this traditional method requiresalmost three square inches of material to cover every square inch of atray of surgical instruments.

The present invention encompasses a disposable multi-panel sterilizationassembly which addresses the problems generally described above. Anexemplary multi-panel sterilization assembly 100 is illustrated in FIG.6.

The multi-panel sterilization assembly includes a barrier panel 102composed of a permeable sheet material 104 having barrier properties(e.g., a barrier fabric), panel attachment means 106 for securing thebarrier panel 102 into a package; and a fold protection panel 108.Generally speaking, the “barrier panel” is the portion of a multi-panelsterilization assembly that is formed from a material that issufficiently permeable to permit a sterilizing gas to pass through it toeffect sterilization and has barrier properties sufficient maintain thatcontent in an aseptic condition after sterilization. A barrier panelshould also be sufficiently flexible or conformable to that it isconfigured to receive and subsequently enfold or enclose content to besterilized thereby forming a package. Generally speaking, the barrierpanel may be a barrier fabric. The “fold protection panel” is theportion of a multi-panel sterilization assembly that is formed from amaterial covers and protects at least a portion of the folded edges ofthe barrier panel. The fold protection panel is the last panel or partof the multi-panel sterilization assembly that is folded or wrappedaround the package formed by the barrier panel around content to besterilized and the first part of the multi-panel sterilization assemblythat is unfolded or unwrapped.

The barrier panel includes: a first surface 110 and a second opposingsurface 112; a first end 114 generally adjacent or adjoining apre-determined fold line 116; a second end 118 opposite the first end114; a first edge 120 that is generally perpendicular to thepre-determined fold line 116; a second edge 122 that is generallyopposite the pre-determined fold line 116; and a third edge 124 that isgenerally perpendicular to the pre-determined fold line 116. The“pre-determined fold line” is a line or region generally defined by thefirst end 114 of the barrier panel. Generally speaking, thepredetermined fold line is offset from the boundary or transitionbetween the barrier panel and the fold protection panel towards thecenter or midpoint of barrier panel 102. The pre-determined fold line116 identifies the desired location for placing the content to besterilized at the first end 114 of the barrier panel 102. The offsetserves to provide a sufficient amount of barrier panel that the contentto be sterilized is fully surrounded by the barrier panel after foldingis complete. The pre-determined fold line 116 may be offset from theboundary or transition by about 0.5 inch (˜13 mm) to about 2 inches (˜51mm). Desirably, the pre-determined fold line is offset by about 1 inch(˜25 mm). The pre-determined fold line may be in the form of a seam (orseams) such as, for example, a stitched seam, an ultrasonic bond seam,adhesive bond seam, thermo-mechanical bond seam (e.g., a bar seal seam)or combinations thereof, that results from joining layers or pliestogether to form the barrier panel and the fold protection panel—or theseam(s) may result from joining pieces together if the barrier and foldprotection panels are discrete pieces. Alternatively and/oradditionally, the predetermined fold line may be identified by printing,or by an imprint such as a thermo-mechanical bond line (e.g., bar sealbond line) or pattern or other indicia, or identified by a crease orother suitable mark. The pre-determined fold line may be an intermittentline or indicia and it may be provided directly on the barrier panel orit may be provided on one or reinforcement elements if such are present.

As noted above, an important feature of the predetermined fold line 116is that it helps delineate where the content to be wrapped andultimately sterilized should be placed. That is, content to be wrappedand sterilized should be placed adjacent only one side of thepredetermined fold line. As discussed subsequently, other features ofthe present invention signal to a user which side of the pre-determinedfold line is the appropriate side to place content. Yet another featureof the predetermined fold line 116 is that it helps defines a boundary,reference line or limit for the user during the wrapping of content tobe sterilized. That is, during wrapping of content to be sterilized, aspart of the barrier panel is brought over the content to be sterilized,that part of the barrier panel should not be extended substantiallyacross or beyond the predetermined fold line 116. In contrast toconventional sterilization wrap systems where the content is placed atthe center of the sterilization barrier, the multi-panel sterilizationassembly required placement at the pre-determined fold line near theboundary or edge of the barrier panel. This is initiallycounterintuitive for users and is quite different from conventionalsterilization wrap systems.

While the barrier panel 102 of FIG. 6 is generally shown as having asquare shape, the barrier panel 102 may be rectangular or may desirablyhave additional edges to define a non-square or non-rectangular shape.Portions of the edges may be arcuate or may otherwise be non-linear.Alternatively and/or additionally, the first edge 120 and the third edge124 may converge or diverge so the edges are not parallel, therebydefining a barrier panel 102 having a trapezoidal shape. It is alsocontemplated that other combinations of opposite edges may converge ordiverge.

For example and referring to FIG. 7A, the barrier panel may have afourth edge 126 to define a non-square or non-rectangular shape. In suchan exemplary configuration, the two edges 122 and 126 are generallyopposite the pre-determined fold line 116 such that the second edge 122and the fourth edge 126 form an apex or vertex. Thus, the barrier panel102 may have a first surface 110 and a second opposing surface 112; afirst end 114 generally defining a pre-determined fold line 116; asecond end 118 opposite the first end 114; a first edge 120 that isgenerally perpendicular to the pre-determined fold line 116; a secondedge 122 that is generally opposite the pre-determined fold line 116; athird edge 124 that is generally perpendicular to the pre-determinedfold line; and a fourth edge 126 located between the second edge 122 andthe third edge 124.

Referring to FIGS. 8A and 8B, the barrier panel 102 may have a fourthedge 126 and a fifth edge 128 to define a non-square or non-rectangularshape such that, for example, the fourth edge 126 and a fifth edge 128generally converge toward the second edge 226 such that the second end118 of the barrier panel is narrower than the first end 114 of thebarrier panel. Thus, the barrier panel 102 may have a first surface 110and a second opposing surface 112; a first end 114 generally defining apre-determined fold line 116; a second end 118 opposite the first end114; a first edge 120 that is generally perpendicular to thepre-determined fold line; a second edge 122 that is generally parallelto the pre-determined fold line 116; a third edge 124 that is generallyperpendicular to the pre-determined fold line 116; a fourth edge 126located between the second edge 122 and the third edge 124; and, a fifthedge 128 located between the first edge 120 and the second edge 122. Thebarrier panel has a first width “W1” that is the distance from the firstedge 120 to the third edge 124 in the first end 114 (e.g., preferablymeasured along the pre-determined fold line 116) and a second width “W2”that is the distance from the fourth edge 126 to the fifth edge 128(e.g., preferably measured between the locations where the fourth edge126 and the fifth edge 128 meet the second edge 122. The barrier panelalso has a length “L” that is the distance from the first end 114 (fromthe pre-determined fold line 116) to the second end (e.g., at the secondedge 122). The barrier panel also has a midpoint “M” along the length“L” and extending between the first edge 120 and the third edge 124 or,in some embodiments, the fourth edge 126 and the fifth edge 128 togenerally delineate the barrier panel 102 into a content receivingregion 130 extending from the pre-determined fold line 116 to themidpoint “M” and a content covering region 132 extending from themidpoint “M” to the second edge 122″. Of course, it is contemplated thatadditional edges may be added or that edges may be curvilinear or mayinclude curvilinear portions.

Referring again to FIG. 6, the barrier panel 102 may have a width “W”that is the distance from the first edge 120 to the third edge 124 and alength “L” that is the distance from the first end 114 to the second end118. According to an aspect of the invention, the barrier panel has amidpoint “M” along the length “L” which spans or runs between the firstedge 120 and the third edge 124 to generally delineate the barrier panel102 into a content receiving region 130 extending from thepre-determined fold line 116 to the midpoint “M” and a content coveringregion 132 extending from the midpoint “M” to the second edge 124.Generally speaking the content receiving region is the portion of thebarrier panel onto which a tray or other content to be sterilized isinitially placed. Unlike conventional sterilization wrap in which a trayor content to be sterilized is placed in the central portion of thebarrier material that forms the sterilization wrap, the contentreceiving region is between the first end and the midpoint of thebarrier panel. This asymmetric placement on the barrier panel is notintuitive. The content covering region is the portion of the barrierpanel that is folded over the content after the content has been placedon the content receiving region.

In an aspect of the invention, the barrier panel of the variousillustrated configurations may have a width of from about 12 inches (˜30cm) to about 50 inches (˜127 cm). Desirably, the barrier panel may havea width of from about 18 inches (˜46 cm) to about 40 inches (˜102 cm).Even more desirably, the barrier panel may have a width of from about 20inches (˜51 cm) to about 30 inches (˜76 cm). The barrier panel may havea length of from about 7 inches (˜18 cm) to about 50 inches (˜127 cm).Desirably, the barrier panel may have a length of from about 15 inches(˜39 cm) to about 40 inches (˜102 cm). Even more desirably, the barrierpanel may have a length of from about 25 inches (˜64 cm) to about 30inches (˜76 cm).

According to an aspect of the invention, the surface area of the contentreceiving region 130 may be from about 25 percent to about 49 percent ofthe total surface area of the barrier panel 102. For example, thesurface area of the content receiving region 130 may be from about 35percent to about 45 percent of the total surface area of the barrierpanel 102. This is important because the content covering portion of thebarrier panel should be larger to provide additional surface area toproperly cover the content.

The multi-panel sterilization assembly 100 includes a panel attachmentmeans 106 located on the first surface 110 between the pre-determinedfold line 116 and the midpoint “M” of the barrier panel. The panelattachment means 106 is desirably at or near the first edge 120 and/oror the third edge 124 of the barrier panel. Although the panelattachment means 106 is illustrated at or near both the first edge 120and the third edge 124 of the barrier panel, the panel attachment means106 may be at or near only one of these edges.

The panel attachment means 106 may be located at and extend from thefirst edge 120 and the third edge 124 of the barrier panel as generallyillustrated in FIGS. 6 and 7A and 7B. Alternatively and/or additionally,the panel attachment means 106 may be located generally near the firstedge and/or the third edge as illustrated in FIG. 8A and FIG. 9A. Thepanel attachment means may be one large element or a number of discreteelements. Exemplary panel attachment means include, but are not limitedto, adhesive tape, double-sided adhesive tape, cleavable release tapes,layered release tapes, cohesive materials, hook and loop fasteningsystems, mechanical fastening systems including, but not limited to,snaps, clips, magnets, catches, slots and tabs, and combinationsthereof. For example, the panel attachment means may be one or morelengths of adhesive tape having at least an end or portion that isstitched, ultrasonically bonded, thermo-mechanically bonded or adheredor adhesively bonded to the barrier panel. Desirably, the panelattachment means is a barrier panel attachment means that is located onthe barrier panel and is used to join one or more edges of the barrierpanel to itself. It has been found that barrier panel attachment meansmay be a double sided tape having the same or different levels ofadhesive or tack strength of adhesive on each side. Alternatively and/oradditionally, the panel attachment means may have a double sided tapestructure in which the central layer sandwiched by the adhesive is asplittable or separable material such as a splittable paper, splittablelaminate, splittable foam, cleavable paper, cleavable release structure,cleavable foam or other cleavable or separable laminate. Exemplarysplittable or cleavable materials are disclosed at, for example, U.S.Pat. No. 5,702,555 issued to Caudal et al. on Dec. 30, 1997; U.S. Pat.No. 4,310,127 issued to Frye on Jan. 12, 1982; U.S. Pat. No. 3,675,844issued to Sorrell on Jul. 11, 1972; and U.S. Pat. No. 2,205,956 issuedto Humphner on Jun. 25, 1940; the contents of which are incorporated byreference.

According to an aspect of the invention, the panel attachment means 106may be in the form of an adhesive fastening tab or tape closure systemsuch as the various types frequently used on diapers, incontinentgarments and similar products. An exemplary tape closure system may befound at, for example, U.S. Pat. No. 4,410,325 issued to Lare on Oct.18, 1983; the contents of which are incorporated by reference. Thissystem utilizes an adhesive fastening tab or tape closure system(referred to herein as a “tape”) that is folded back on itself and whichhas a first end or portion that is attached to the article (e.g., onepart of a garment). During use, the tape is unfolded to reveal anexposed adhesive surface at least at a second end or portion of the tapewhich is then adhered to a different part of the article (e.g., a secondpart of the garment) to secure the two parts of the garment in thedesired configuration. Generally speaking, the first end of the tapepanel attachment means 106 would be secured at or near the first edge120 of the barrier panel and the second end of the tape panel attachmentmeans 106 would be folded back onto the first end. An additional panelattachment means 106 may be secured at or near the third edge 124 of thebarrier panel in a similar manner. During use, the tape panel attachmentmeans 106 would be unfolded to reveal an exposed adhesive surface orsurfaces at least at the second end of the panel attachment means 106.The exposed adhesive surface(s) of the panel attachment means at firstedge 120 and/or third edge 124 of the barrier panel would be used tosecure those portions of the barrier panel to each other and/or to otherportions of the barrier panel after the barrier panel is folded aboutcontent to be sterilized. In such a configuration, an optionalattachment zone 305 may be utilized. An exemplary optional attachmentzone 305 is indicated by broken lines in FIG. 8B and in FIG. 9B. Inembodiments that utilize adhesive or cohesive materials for the panelattachment means, the attachment zone 305 may be an applied film, a moresecurely bonded portion of a nonwoven fabric, a separate piece of amaterial, a coating or the like that provides a suitable surface for theadhesive to bond securely so folded barrier panel does not “pop” open orrelease when it should not do so. The attachment zone 305 may beconfigured to signal to a user the appropriate location or locations tosecure the panel attachment means. In such configuration, the attachmentzone 305 may be combined with or may incorporate indicia such as color,texture, alphanumeric characters or the like (illustrated in FIG. 8B as“I”) to direct a user. More importantly, the attachment zone 305 can beconfigured to provide a suitable surface such that the fTorce requiredto release the panel attachment means 106 is carefully controlled topreserve aseptic opening, avoid tearing or shredding of the barrierfabric, provide a satisfactory level of resistance to sheer forces,and/or provide a satisfactory or controlled level of resistance to peelforces.

Another exemplary tape closure system may be found at, for example, U.S.Pat. No. 4,585,450 issued to Rosch et al. on Apr. 29, 1986; the contentsof which are incorporated by reference. This system utilizes an adhesivefastening tab or tape closure system (referred to herein as a “tape”)that includes a secondary tape element and a primary tape element. Thetape has a first end or portion that is attached to the article (e.g.,one portion of a garment). The second end or portion contains thesecondary tape element and primary tape element. During use, an adhesivesurface of the primary tape element is exposed. The adhesive surface ofthe primary tape element is then adhered to a different part of thearticle (e.g., a second part of the garment) to secure the two parts ofthe garment in the desired configuration. An adhesive bond between theprimary tape element and the secondary tape element has less strengththan the adhesive bond between the primary tape element and the secondpart of the garment or article such that the bond between the primarytape element and secondary tape element may be reliably separated,repeatedly if necessary.

Generally speaking, the first end or a first side of a panel attachmentmeans 106 would be secured at or near the first edge 120 of the barrierpanel and the second end or the second side of the tape panel attachmentmeans 106 would be folded back onto the first end or otherwise coveredby a release element. An additional panel attachment means 106 may besecured at or near the third edge 124 of the barrier panel in a similarmanner. During use, the primary tape element of the panel attachmentmeans 106 would be unfolded or uncovered to reveal an exposed adhesivesurface(s) at least at the second end or second side of the panelattachment means 106. The exposed adhesive surface(s) of the primarytape element of would be used to join the first edge 120 and/or thirdedge 124 of the barrier panel to each other or to other portions of thebarrier panel after the barrier panel is folded about content to besterilized. In such a configuration, the adhesive bond between theprimary tape element and the secondary tape element has less strengththan the adhesive bond between the primary tape element and the portionof the barrier panel to which it is adhered such that the bond betweenthe primary tape element and secondary tape element may be reliablyseparated, repeatedly if necessary. In some respects, the primary tapeelement may function as an attachment zone. That is, after the primarytape element is adhered to the barrier panel to secure the barrier panelin a folded configuration, the primary tape element may provide asuitable surface such that the force required to overcome the adhesivebond between the primary tape element and the secondary tape element iscarefully controlled to preserve aseptic opening, avoid tearing orshredding of the barrier fabric, provide a satisfactory level ofresistance to sheer forces, and/or provide a satisfactory or controlledlevel of resistance to peel forces. In another aspect, the attachmentzone 305 as describe previously or in the form of the primary tapeelement may be used to allow a worker to re-open the wrapped barrierpanel prior to inspect contents prior to sterilization and thenre-attach the panel attachment means without having to destroy themulti-panel sterilization assembly.

As another example, the panel attachment means may be a length of fabricsuch as nonwoven fabric having an end or portion that is stitched,ultrasonically bonded, thermo-mechanically bonded or adhered oradhesively bonded to the barrier panel and having a hook fastener from ahook and loop fastening system joined to the other end. It iscontemplated that the barrier fabric itself may function as the loopcomponent of a hook and loop fastening system such as hook and loopfastenings systems available as VELCRO® brand fastener products fromVelcro Industries B.V. Other exemplary hook systems may be used such asthe hook system described in U.S. Pat. No. 5,315,740 issued to Nestegardwhich relates to hooks having small dimensions so they engage low costloop materials such as nonwoven webs.

It is contemplated that various elements or components of the panelattachment means, may be integrally formed, such as by molding,co-extrusion or the like, along with any associated substrate layer. Forexample, the individual hook elements may be integrally formedsimultaneously with a hook base-layer by coextruding the base layer andhook elements from substantially the same polymer material.

According to an aspect of the invention, the panel attachment means 106is joined to the first surface 110 of the barrier panel 102 at apre-determined position 140 to identify or distinguish the contentreceiving region 130 of the barrier panel 102 from the content coveringregion 132 as generally illustrated in FIGS. 6 and 9A. The location ofthe panel attachment means 106 at the pre-determined position 140 alsosignals to a user an optimum zone or region within the content receivingregion 130 to place content. This may be highlighted by indicia on theassembly and/or instructions (illustrated in FIGS. 6, 8B, 9A and 9B as“I”) on the assembly or which accompany the assembly and which may beposted in the workplace or displayed at a wrapping station.

Referring to FIGS. 8A and 9A, the panel attachment means 106 isdesirably a double sided tape having a length that is greater than itswidth. For example, the panel attachment means may be a double sidedtape having a length that more than two times great than its width. Asanother example, the panel attachment means may be a double sided tapehaving a length that is four times great than its width to eight timesgreater than its width. Alternatively and/or additionally, theconfiguration of the panel attachment means may be a series of tapesquares arranged along or near the first edge 120 and the third edge124. The portion of the panel attachment means 106 closest to thepre-determined fold line 116 is desirably less than about 3 inches fromthe pre-determined fold line 116. More desirably, the portion of thepanel attachment means 106 closest to the pre-determined fold line 116is desirably less than about 2 inches from the pre-determined fold line116. For example, the portion of the panel attachment means 106 closestto the pre-determined fold line 116 may be about 1 inch to about ½ inchfrom the pre-determined fold line 116.

Referring again to FIG. 6, the fold protection panel 108 of themulti-panel sterilization assembly 100 is in juxtaposed communicationwith the barrier panel 102. That is, the fold protection panel 108 is inside-by-side relationship with or adjoins the barrier panel 102.Generally speaking, the fold protection panel 108 may be any suitablematerial but desirably is formed of a permeable sheet material.According to the invention, the fold protection panel includes aproximal end 142 generally adjacent the pre-determined fold line 116; adistal end 144 generally opposite the proximal end 142; and at least afirst edge 146 and a second edge 148 extending from the proximal end 142to the distal end 144. According to the present invention, the foldprotection panel may have additional edges. For example and withreference to FIG. 7A, the fold protection panel may include at least athird edge 150 located at or along its distal end 144. As yet anotherexample and referring now to FIG. 8A, the fold protection panel mayinclude at least a third edge 150 located at or along its distal end 144and a fourth edge 152 and a fifth edge 154.

Generally speaking, the fold protection panel may be a lightweightmaterial such as a lightweight laminate of spunbond nonwoven material ora lightweight laminate of spunbond nonwoven material and meltblownnonwoven material. As such, the fold protection panel does not need toprovide a higher level of barrier properties like the material thatforms the barrier panel. The fold protection panel may be configured soit has barrier properties. For example, the fold protection panel may beformed of the same material as the barrier panel. It is contemplatedthat the fold protection panel may be a single layer of spunbondnonwoven material.

In an aspect of the invention, the fold protection panel desirably has awidth that is the distance from the first edge to the second edge and alength that is the distance from the proximal end to the distal end. Thefold protection panel may have a width of from about 12 inches (˜30 cm)to about 50 inches (˜127 cm). Desirably, the fold protection panel mayhave a width of from about 18 inches (˜46 cm) to about 40 inches (˜102cm). Even more desirably, the fold protection panel may have a width offrom about 20 inches (˜51 cm) to about 30 inches (˜76 cm). The foldprotection panel may have a length of from about 6 inches (˜15 cm) toabout 30 inches (˜76 cm). Desirably, the fold protection panel may havea length of from about 8 inches (˜20 cm) to about 20 inches (˜51 cm).Even more desirably, the fold protection panel may have a length of fromabout 12 inches (˜30 cm) to about 15 inches (˜38 cm).

During use, panel attachment means 106 are used to join the barrierpanel's first edge 120 and third edge 124 to a portion of the contentcovering region 132 after the barrier panel 102 has been folded at ornear its midpoint “M” such that its second end 118 is brought near itsfirst end 114. It is contemplated that in some embodiments, the panelattachment means 106 may be used to join the barrier panel's first edge120 and third edge 124 to each other.

According to an aspect of the invention, it is important that theadhesive force or the engagement force at which the panel attachmentmeans join the respective edges of the barrier panel to the contentcovering region of the barrier panel or to the edges themselves shouldbe sufficient to secure the barrier panel around the content therebyforming a package that is robust and able to withstand normal handlingbefore as well as after sterilization.

In exemplary arrangements, especially where there are sufficiently highlevels of engagement shear force provided by the panel attachment means,the fastening engagement may provide a peel force value of not less thana minimum of about 5 grams-force (gmf) (about 0.012 lbs-force) betweenthe panel attachment means and the other portion of the barrier panelthat it secures together. In further arrangements, the fasteningengagement may provide a peel force value of between about 6 gmf andabout 50 gmf to provide improved advantages. In desired configurations,the fastening engagement may provide a peel force value about betweenabout 10 gmf and about 30 gmf between the panel attachment means and theother portion of the barrier panel that it secures together. Moredesirably, the peel force value may be between about 15 gmf and about 20gmf. Generally speaking, the peel force should not be more than about100 gmf, and desirably is not more than about 75 gmf to further provideimproved benefits. When the peel force is greater than these values,there is difficulty opening/unwrapping the package containing sterilizedcontents in an aseptic manner.

The engagement force between the panel attachment means and the otherportion of the barrier panel that it secures together may additionallyprovide a shear force value that is desirably greater than about 5,000gmf for a panel attachment means having dimensions of about 4 by 1inches (˜102 by ˜25 mm). Generally speaking, the resistance to shearforce should not be less than about 750 gmf per square inch of the areaof engagement between the panel attachment means and the other portionof the barrier panel that it secures together. Desirably, the shearforce is not less than about 1,000 gmf/square inch, and more desirably,is not less than about 2,000 gmf/square inch. Even more desirably, theshear force is not less than about 2,500 gmf/square inch. In furtheraspects, the shear force can be up to about 4,400 gmf/square inch, ormore. Alternatively, the shear force is not more than about 3,900gmf/square inch, and optionally is not more than about 3,500 gmf/squareinch to provide improved performance.

The peel force value can be determined utilizing the procedure set forthbelow in the Examples section. Alternatively, the peel force value canbe determined in accordance with standard procedure ASTM D-5170,approved Sep. 15, 1991 and published November 1991.

The shear force value can be determined utilizing the procedure setforth below in the Examples section. Alternatively, the shear forcevalue can be determined in accordance with standard procedure ASTMD-5170, approved Sep. 15, 1991 and published November 1991. The testspecimen is composed of the panel attachment means and the portion ofthe barrier panel to which it secures. The test specimen length andwidth typically correspond to the length and width employed to conductthe subsequently described testing for peel force value. During testing,the test specimen length is aligned perpendicular to the direction inwhich a shear force is typically applied to the panel attachment means(e.g., double sided tape fastener) during the ordinary use of thearticle with which the fastener is employed. The specimen “width” isperpendicular to the specimen length. That is, shear force is typicallyapplied across the width of the specimen (i.e., perpendicular to thelength) for a specimen having a length that is greater than itswidth—which is the configuration illustrated in FIGS. 8A and 9A.

It should be readily appreciated that the adhesive force or theengagement force at which the panel attachment means join the respectiveedges of the barrier panel to the content covering region of the barrierpanel or to the edges themselves should be less than the peel strengthof the bond that is used to join the panel attachment means to theunderlying barrier panel during construction of the assembly. Forexample, the peel strength of the bond (e.g., adhesive, mechanical,thermo-mechanical, ultrasonic, etc.) that is used to join the panelattachment means to the underlying barrier panel during constructionshould be much greater than about 400 gmf for a panel attachment meanshaving a dimension of about 4 inches by 1 inch (about 10 cm by 2.5 cm).Desirably, the peel strength of the bond that is used to join the panelattachment means to the underlying barrier panel during constructionshould be greater than about 400 gmf per square inch of the area ofengagement between the panel attachment means and the barrier. Forexample, the bond strength may be more than 1000 gmf/square inch, andmay be more than 4,000 gmf/square inch.

Referring now to FIGS. 9A through 9E (and with additional reference toFIG. 8A), there is illustrated an example of a multi-panel sterilizationassembly in an exemplary sequence of folding. FIG. 9A illustrates amulti-panel sterilization assembly 100 composed of barrier panel 102which cooperates with the fold protection panel 108 and the panelattachment means 106 on the first surface 110 so the barrier panel 102can be folded around the content 200 to form a package (such as thepackage 202 generally illustrated in FIG. 9E). The barrier panel 102 isthe portion of the flexible multi-panel sterilization assembly 100 thatcontacts and covers the content 202. The content 200 is placed in thecontent receiving 130 which is generally defined by the panel attachmentmeans 106 on the first surface 110 of the barrier panel 102.

As generally illustrated in FIG. 9B, the second end 118 of the barrierpanel 102 is folded up at the midpoint “M” and brought to the first end114 so the content covering region 132 of the barrier panel 102 extendsover the content 200. As shown in FIG. 9B, the width of the barrierpanel at the second end 118 is less than the width of the barrier panelat the first end 114. This is important when the panel attachment means106 are located directly on the barrier panel as shown in FIGS. 8A and9A (rather than extending outward from the edges as illustrated in FIGS.7A and 7B) because it provides a configuration of the fourth edge 126and the fifth edge 128 that allows access to the panel attachment means106 after the second end 118 is brought up to the first end 114.

In some embodiments of the present invention, a pull tab or tail 300 isextends from the second end 118 so that the pull tab or tail 300 ispositioned to be accessible during the initial steps of unfolding orunwrapping a wrapped package. The pull tab or tail 300 desirably extendsfrom or is joined to the second end 118 of the barrier panel on thesecond opposing surface 112 of the barrier panel 102. Referring brieflyto FIG. 7B, there is shown a configuration in which the pull tab or tail300 is unitary or integral with the barrier panel. FIG. 7C illustratesthat pull tab or tail 300 on the second opposing surface 112 of thebarrier panel 102. The distal end (i.e., the loose end) of the pull tabor tail 300 is desirably secured to the barrier panel with a lightadhesive or an adhesive tab or sticker such that the pull tab or tail300 does not flop around during wrapping and is in an appropriateposition during unwrapping.

Referring now to FIG. 9C, that illustration shows that the third edge124 of the barrier panel 102 is folded over the second end 118 (afterthe second end 118 is brought up to the first end 114). While notnecessarily shown to scale, the third edge 124 of the barrier panel 102after folding does not extend very far toward the middle of theassembly.

FIG. 9D illustrates that the first edge 120 of the barrier panel 102 isfolded over the second end 118. While not necessarily shown to scale,the first edge 120 of the barrier panel 102 upon folding does not extendvery far toward the middle of the assembly. Accordingly, it is evidentthat the third edge 124 and the first edge 120 generally do not overlap.Unlike conventional sterilization wrap in which the edges areintentionally overlapped as generally illustrated in FIGS. 4 and 5, theedges 120 and 124 of the barrier panel are separated by a distance. Thisdifference highlights the importance of the panel attachment means 106to hold the folded edges 120 and 124 of the barrier panel 102 in placeabout the content. Moreover, having these edges generally exposedhighlights the importance of the fold protection panel 108.

Referring now to FIG. 9E, the fold protection panel 108 is folded at thepre-determined fold line 116 bringing its distal end 144 over the secondend 118 of the barrier panel. In some embodiments, a portion of thematerial adjacent the first edge 120 and the third edge 124 may bevisible. With this configuration, the actual edges 120 and 124 of thebarrier panel 102 are fully covered so the edges themselves are lesssusceptible to being accidently pulled open or breached during normalhandling of the package. The fold protection panel is typically securedutilizing conventional tape that is used with sterilization wrap.Desirably, the fold protection panel covers the edges of the barrierprotection panel after it is folded around the content to be sterilizedto form a package. The fold protection panel covers these edges toprevent a worker inadvertently opening the folded barrier protectionpanel. In addition, the fold protection panel shields the edges fromsnags, pulls or other phenomenon that could impart a peel force to theseedges that would cause the panel attachment means to detach. That is,the configuration of the multi-panel sterilization assembly utilizes thefold protection panel to protect exposed edges of the barrier panelafter the barrier panel has been folded around content to be sterilizedto form a package.

According to the present invention, the barrier panel may be composed ofat least one layer of a breathable nonwoven material. Desirably, thebreathable nonwoven material is a laminate composed of a layer ofspunbonded filaments, a layer of meltblown fibers, and a layer ofspunbonded filaments—also called spunbonded-meltblown-spunbondedmaterial. The method of making these layers is known and described incommonly assigned U.S. Pat. No. 4,041,203 to Brock et al which isincorporated herein in its entirety by reference. The material of Brocket al is a three layer laminate of spunbonded-meltblown-spunbondedlayers which is also commonly referred to by the acronym “SMS”. The twoouter layers of SMS are a spunbonded material made from extrudedpolyolefin fibers, or filaments, laid down in a random pattern and thenbonded to one another. The inner layer is a meltblown layer also madefrom extruded polyolefin fibers generally of a smaller diameter than thefibers in the spunbonded layers. As a result, the meltblown layerprovides increased barrier properties due to it fine fiber structurewhich permits the sterilizing agent to pass through the fabric whilepreventing passage of bacteria and other contaminants. Conversely, thetwo outer spunbonded layers provide a greater portion of the strengthfactor in the overall laminate. The laminate may be prepared using anintermittent bond pattern that is preferably employed with the patternbeing substantially regularly repeating over the surface of thelaminate. The pattern is selected such that the bonds may occupy about5-50% of the surface area of the laminate. Desirably, the bonds mayoccupy about 10-30% of the surface area of the laminate. Othercombinations and variations of these materials are contemplated. As anon-limiting example, the inner layer may contain two meltblown layerssuch that the material may be called “SMMS”.

When the barrier panel is composed of or incorporates SMS material(s),the basis weight of the SMS material(s) may be from 1 ounce per squareyard or “osy” which is approximately (33 grams per square meter or“gsm”) to about 3 osy (100 gsm). For example, the basis weight of theSMS material(s) may be from 1.2 osy (40 gsm) to about 2 osy (67 gsm). Asanother example, the basis weight of the SMS material(s) may be from 1.4osy (47 gsm) to about 1.8 osy (60 gsm). The basis weight may bedetermined in accordance with ASTM D3776-07. Multiple plies or layers ofSMS material may be used to provide basis weights ranging from about 2osy (67 gsm) to about 5 osy (167 gsm).

The permeability of the barrier panel may range from 25 to about 500cubic feet per minute (CFM) as characterized in terms of Frazierpermeability. For example, the permeability of the barrier panel mayrange from 50 to about 400 cubic feet per minute. As yet anotherexample, the permeability of the barrier panel may range from 100 toabout 300 cubic feet per minute. The Frazier permeability, whichexpresses the permeability of a material in terms of cubic feet perminute of air through a square foot of area of a surface of the materialat a pressure drop of 0.5 inch of water (or 125 Pa), was determinedutilizing a Frazier Air Permeability Tester available from the FrazierPrecision Instrument Company and measured in accordance with FederalTest Method 5450, Standard No. 191A. When the barrier panel is composedof or incorporates SMS material(s) have basis weights ranging from about1 osy (33 gsm) to about 2.6 osy (87 gsm), the permeability of thebarrier panel may range from about 20 cubic feet per minute to about 75cubic feet per minute when determined generally in accordance with ISO9237:1995 (measured with an automated air permeability machine using a38 cm² head at a test pressure of 125 Pa, - exemplary air permeabilitymachine is TEXTEST FX 3300 available from TEXTEST AG, Switzerland). Ifmultiple plies or layers of SMS material are used to provide basisweights ranging from about 2 osy (67 gsm) to about 5 osy (167 gsm), thepermeability of the barrier panel may range from about 10 cubic feet perminute to about 30 cubic feet per minute when determined generally inaccordance with ISO 9237:1995.

As noted above, the flexible multi-panel sterilization assembly 100 mayinclude at least one pull tab 300 extending from the second end 118 ofthe barrier panel 102. The pull tab 300 may be formed of the samematerial as the barrier panel or may be formed of one or more differentmaterials. The pull tab is a feature that can be grasped by a personunfolding a sterilized package formed of a folded flexible multi-panelsterilization assembly containing sterilized content withoutcompromising the sterile field formed by the unfolded content-contactingportions of the barrier panel. The pull tab 300 may be attached to thebarrier panel or it may be integral or unitary with the barrier panel.In an aspect of the invention, the barrier panel at or adjacent theedges near the pull tab 300 may be bonded together utilizing a seam suchas, for example, a stitched seam, an ultrasonic bond seam, adhesive bondseam, thermo-mechanical bond seam (e.g., a bar seal seam) orcombinations thereof to provide sufficient stiffness, rigidity orsupport to that portion of the barrier panel so that folding or creasingof the barrier panel is reduced or eliminated when force is applied tothe pull tab 300 during unwrapping. This is important to preserve thesterility of the contents during unwrapping. For example, the secondedge 122 and the fourth edge 126 illustrated in FIG. 7B may be partiallyor substantially bonded to provide such a configuration. As anotherexample, the second edge 122 illustrated in FIG. 8A may be partially orsubstantially bonded to provide the desired configuration. As yetanother example, the second edge 122 and/or the fourth edge 126 andfifth edge 128 illustrated in FIG. 8A may be partially or substantiallybonded to provide the desired configuration.

In an embodiment of the invention, the sterilization assembly mayfurther include one or more discrete reinforcement elements in thecontent receiving region. In addition to reinforcing the barrier panel,the reinforcement element may define an area for receiving content to besterilized. The reinforcement elements may include one or more layers ofmaterials selected from fibrous webs, impermeable films, permeable orporous films, apertured films, foams and combinations thereof. Forexample, fibrous webs may include those that are woven and nonwoven.Woven webs may include natural or synthetic materials or blends of thesame. As examples, natural materials could be weaves of cotton yarn, andsynthetic materials could be weaves of polypropylene, polyester, ornylon yarn and the like. Nonwoven webs may include, for example,spunbond, meltblown, carded webs, wet formed or airlaid webs, orlaminates of the same (e.g., spunbond/meltblown/spunbond). Such nonwovenwebs may also include natural or synthetic materials or blends of thesame. The reinforcement elements include one or more layers of materialselected from permeable or impermeable films or laminates of the same.Permeable films may be apertured or be microporous. Apertured films maybe obtained through mechanical aperturing, vacuum aperturing, or othercommercially available techniques. Microporous films and other similarfilms may be produced as generally described at, for example, U.S. Pat.No. 5,695,868; U.S. Pat. No. 5,698,481; U.S. Pat. No. 5,855,999; andU.S. Pat. No. 6,277,479; the contents of which are incorporated hereinby reference. Impermeable films can be monolayer or coextruded and canbe comprised of film materials including, for example, polyethylenes,polypropylenes, copolymers thereof, vinyls, metal foils, and the like.It should also be noted said films may also be laminated with fibrouswebs, described above.

Reinforcement elements are discrete zones of the barrier panel ofcontaining additional material or treatments to reduce the likelihoodthat the barrier panel will be compromised by pressure cuts, pressureholes, tears or the like in the locations where the content is likely toconcentrate forces against the material(s) of the barrier panel. It isenvisioned that relative to the material(s) of the barrier panel, thereinforcement elements can be less permeable or even impermeable to hotair, steam, or other sterilization gas, while still allowing for propersterilization and removal of sterilant gas. It has been found thatacceptable sterilization and removal of sterilant gas will take place ifthe permeability of the sterilization package web is greater than about25 cubic feet per minute (cfm) as characterized in terms of Frazierpermeability. As such, a reinforcement element material that isimpermeable or less permeable than the sterilization package material isacceptable, as long as the overall sterilization package is adequatelypermeable (i.e., greater than about 25 cfm). If an impermeable or lesspermeable reinforcement element material is desirable, the permeabilityof the overall sterilization package can be varied by changing the areacovered by the reinforcement element. It is desirable that thesterilization package web maintain an overall permeability of at leastabout 25 cfm.

The reinforcement elements may also be configured to identify thecontent receiving region 130 of the barrier panel 102. Alternativelyand/or additionally the reinforcement elements may be configured tocooperate with the panel attachment means to identify the contentreceiving region 130 of the barrier panel 102. For example, thereinforcement elements may be in the form of discrete shapes placedwithin the content receiving region. FIGS. 10A through 10D areillustrations of exemplary flexible multi-panel sterilization assemblies100 composed of a barrier panel 102, panel attachment means 106 and afold protection panel 108 and which further include reinforcementelements 302.

FIG. 10A illustrates a flexible multi-panel sterilization assembly 100in which four reinforcement elements 302 are positioned at spaced apartlocations in the content receiving region 130 of the barrier panel 102generally at the locations that correspond to the corners of asterilization tray or similar content. FIG. 10B illustrates a flexiblemulti-panel sterilization assembly 100 in which two reinforcementelements 302 are positioned at spaced apart locations on the barrierpanel 102 extending from the pre-determined fold line 116 to a fourthedge 126 and a fifth edge 128 of the barrier panel 102 generallyopposite the pre-determined fold line 116. The two reinforcementelements 302 are positioned in the content receiving region 130generally at the locations that correspond to the corners of asterilization tray or similar content. FIG. 10C illustrates a flexiblemulti-panel sterilization assembly 100 in which two reinforcementelements 302 are positioned at spaced apart locations on the barrierpanel 102 generally parallel to the pre-determined fold line 116 betweenthe two panel attachment means 106 at or adjacent a first edge 120 and athird edge 124. The two reinforcement elements 302 are positioned in thecontent receiving region 130 generally at the locations that correspondto the corners of a sterilization tray or similar content. FIG. 10Dillustrates a flexible multi-panel sterilization assembly 100 in whichtwo reinforcement elements 302 are positioned at spaced apart locationson the barrier panel 102 and the fold protection panel 108. The tworeinforcement elements 302 extend in generally parallel configurationfrom a distal end 144 of the fold protection panel 108 to a fourth edge126 and a fifth edge 128 of the barrier panel 102. The two reinforcementelements 302 are positioned in the content receiving region 130generally at the locations that correspond to the corners of asterilization tray or similar content. It should be noted that a pulltab or tail 300 is illustrated in FIGS. 10A to 10D as extending out fromunderneath the barrier panel. This representation is merely intended toillustrate that a pull tab or tail 300 may be included and notparticularly how it is preferably configured.

Of course, the reinforcement elements may have a wide variety of shapes,sizes and other configurations. FIGS. 11A and 11B are illustrations ofexemplary reinforcement elements 302. FIG. 11A illustrates reinforcementelements 302 having generally triangular configurations. FIG. 11Billustrates an exemplary reinforcement element 302 composed of severaloverlapping triangular elements. Alternatively and/or additionally, thereinforcement element 302 illustrated in FIG. 11B may be formed by asingle piece of material. Other shapes and configurations arecontemplated such, for example, “H” patterns, “X” patterns, or the like.

In an aspect of the invention, the construction of the disposableflexible multi-panel sterilization assembly may be based on a twoprimary pieces of material. Referring now to FIG. 12, there is shown anillustration of an exemplary disposable flexible multi-panelsterilization assembly 100 in exploded or broken apart view revealing afirst layer 304 of a material and a second layer 306 of material. Inthis configuration, the first layer 304 of material and the second layer306 of material overlap to define the barrier panel 102. Generallyspeaking, these layers may be joined by adhesives, ultrasonic bonding,thermo-mechanical bonding or the like. The layers are desirably joinedat or adjacent at least two of the edges and along the pre-determinedfold line. For example, the layers may be joined along the first edge120 and the third edge 124. The bonding may be a complete seam or theedge may be partially bonded along only one or a few portions of theedge. Alternatively and/or additionally, the bonding may be intermittentor discontinuous along all or a portion of the respective edge. Ofcourse, other edges may also be bonded or the layers may be bondedtogether across all or portions of their entire surface area. The regionwhere there is no overlap of the first layer 304 of material and secondlayer 306 of material forms the fold protection panel 108. Generallyspeaking, the first layer 304 of material and the second layer 306 ofmaterial may be the same material or they may be different materials.For example, the first layer 304 of material may be single layer ormultiple layers of spunbond nonwoven material, a lightweight nonwovenlaminate material, or a material that lacks the level of barrierproperties (or other characteristics) that may be desired for thebarrier panel. The second layer 306 of material desirably has a higherlevel of barrier properties than the first layer 304 of material. Forexample, the second layer 306 of material may be a laminate of nonwovenfabrics such as “SMS” material. The second layer 306 of material mayhave a different color and/or pattern than the first layer 304 ofmaterial. For example, the first layer 304 of material may have a firstcolor (e.g., a blue color), a dark color, or a specific color on a colorscale and the second layer 306 of material may have no color (e.g.,white), a second color (e.g., a light color), or a specific color on acolor scale that contrasts with the first color.

As generally shown in FIG. 12, the first surface 110 of the disposableflexible multi-panel sterilization assembly 100 may be formed of thesecond layer 306 of material and the first layer 304 of material and thesecond opposing surface 112 may be formed of the first layer 304 ofmaterial. It is contemplated that the first surface 110 of thedisposable flexible multi-panel sterilization assembly 100 may be formedof the first layer 304 of material and the second opposing surface 112may be formed of the first layer 304 of material and the second layer306 of material. It is also contemplated that other combinations oflayers may be used such that two layers of material generallycorresponding in size to the first layer of material 304 may sandwich orenclose an intermediate layer of material corresponding in size to thesecond layer of material 306 such that the first surface 110 and thesecond opposing surface 112 are generally the same such that one surfacedoes not reveal two discrete layers of material (i.e., does not showboth the first layer 304 of material and the second layer 306 ofmaterial).

It is contemplated that the color differentiation or contrast betweenthe first layer 304 of material and the second layer 306 of material maybe useful to function as an indicator that barrier properties of thebarrier panel may be compromised.

Referring now to FIG. 13, there is shown an illustration of an exemplarydisposable flexible multi-panel sterilization assembly 100 in explodedor broken apart cross-sectional view revealing a first layer 304 of amaterial and a second layer 306 of material. In this configuration, thefirst layer 304 of material and the second layer 306 of material overlapto define the barrier panel 102. The region where there is no overlap ofthe first layer 304 of material and second layer 306 of material formsthe fold protection panel 108. The cross-sectional view illustratesreinforcement elements 302. The reinforcement elements 302 may bepresent on the first surface 110 to desirably identify the contentreceiving region 130 of the barrier panel 102 between the panelattachment means 106. Alternatively and/or additionally, thereinforcement elements 302 may be located on the second opposing surface112 of the barrier panel.

Sterilization wrap has many modes of failure involving tears, cuts,punctures, holes or other breaches. Any failures may have seriousconsequences. The more common modes of failure are conventionallybelieved to involve tears, holes or cuts initiating from thesterilization tray or other content that is wrapped by or otherwiseenclosed by conventional sterilization wrap fabric. In other words,tears, cuts or holds were believed to begin at the interface between thesterilization tray or other content and the sterilization wrap fabricitself and propagate from the inside of the sterilization wrap fabricpenetrating outwardly through the material ultimately creating a breach.Accordingly, much effort has been expended to develop corner guards andother types of protection that is placed between the sterilization trayor other content and the sterilization wrap.

In an aspect of the present invention, it has been discovered thatpressure holes and pressure cuts of the type in which the fibersadjacent the hole or cut appear to have been fused or “welded” togethermost commonly propagate from the outside of a package (i.e., contentenclosed by sterilization wrap fabric) rather than propagating thesterilization tray or other content that is wrapped by or otherwiseenclosed by conventional sterilization wrap fabric. Accordingly, theapplicants have discovered that locating the reinforcement elements 302on the second opposing surface 112 of the barrier panel provides anunexpected advantage because the second opposing surface 112 of thebarrier panel 102 is the portion of the disposable flexible multi-panelsterilization assembly 100 that does not contact the content (e.g.,sterilization tray) and which typically forms the outside of a wrappedpackage. Reinforcement elements 302 located on the second opposingsurface 112 provide more efficient protection against pressure holes andpressure cuts because the inventors have discovered that pressure holdsand pressure cuts tend to propagate from the outside of a wrappedpackage. While the inventors should not be held to any particular theoryof operation, it has been discovered that pressure cuts and pressureholes are more frequently caused when content enclosed by sterilizationwrap contacts an irregular surface with sufficient force during a singlecontact event or during multiple contact events such that the irregularsurface concentrates the force to generate energy that causes failure.

Such contact events are frequently encountered when an individualwrapped sterilization tray or stacks of wrapped sterilization trays(particularly at overloaded weights) are transported by cart or othersimilar device and the cart or similar device stops abruptly (e.g., dueto impact), encounters bumps or abrupt shocks. Other sources of contactevents occur when wrapped trays are dropped (especially on the edge of acart); when wrapped trays are dragged or pushed across a smooth surface;when a wrapped tray contacts a hard surfaces; and/or when excessivepressure is applied to a wrapped tray. For example, lifting the frontend of a 20 pound tray so that all the weight of the tray is resting onthe back end, and pulling it across the storage shelf before lifting mayproduce pressure cuts. As another example, dropping a wrapped tray (evena small distance) onto an edge of a cart or storage shelf while beingtransported to different areas of the hospital may produce pressureholes.

Generally speaking, the utilization of reinforcement elements reducespressure hole formation for each of the barrier materials tested.Quantitatively, pressure hole formation is reduced between ˜30% and 46%,depending upon what barrier material is tested and the basis weights ofthe barrier material and the reinforcement elements (corner guards).

When using reinforcement elements in conjunction with a relatively lowbasis weight barrier material (e.g., about 1 osy), low basis weightreinforcement elements (e.g., from about 0.1 to about 1 osy) result insubstantial reduction in pressure hole formation in the barriermaterial. Further increasing reinforcement element basis weight (e.g.,to a basis weight of from about 1 to about 2 osy) results in additional,but more modest, reduction in pressure hole formation in the barriermaterial. Further increasing the reinforcement element basis weight(e.g., to a basis weight of greater than about 2 osy) appears to providelittle, if any, additional improvement in reducing pressure holeformation in the barrier material.

While the inventors should not be held to a particular theory ofoperation, a relatively “weak” barrier material (e.g., relatively lowbasis weight) which is not protected by a reinforcing element on theexterior of the barrier material (i.e., the outermost surface of thebarrier material) will eventually fail at the same rate regardless ofhow “strong” (e.g., relatively high basis weight) the reinforcementelements are that might be used on an interior surface (i.e., theinterior surface contacting the content to be sterilized or thesterilized content) of the barrier material.

When using reinforcement elements in conjunction with a moderate basisweight barrier material (e.g., basis weight about 1.8 osy), the use oflow basis weight reinforcement elements (e.g., basis weights from about0.1 to about 1 osy) on the interior surface of the barrier material(i.e., the interior surface contacting the content to be sterilized orthe sterilized content) results in substantial reduction in pressurehole formation in the barrier material. A similar “plateau”, wherefurther increasing the basis weight of the reinforcement element on theinterior surface no longer provides additional benefit to the barriermaterial is believed to exist.

Use of a relatively light weight reinforcement element (˜1 osy) reducespressure hole formation in all basis weights of barrier materials(barrier materials ranging from 1 osy to 2 osy). As the basis weight ofthe barrier material is increased, basis weight of the barrier materialitself becomes the most predominant factor for reinforcement and reducedpressure hole formation. But light weight reinforcement elements stillreduce pressure hole formation in the heaviest barrier materials tested(˜2 osy), as compared to when reinforcement elements are not used.Extrapolation would suggest that a barrier material of 3 osy or greaterwould not benefit from a 1 osy reinforcement element.

Generally speaking, the results of this testing show that PercentFailure decreases as the basis weight of the barrier material isincreased. However, when reinforcing elements are positioned between thesterilization tray and the barrier material, an increase in the basisweight of the combined components (i.e., the barrier material basisweight is constant and reinforcing element basis weight increases)results in a decrease in Percent Failure that levels off at a muchhigher rate of failure than for a barrier material having acorresponding basis weight.

Surprisingly, when reinforcing elements are positioned on the outside ofthe barrier material such that the reinforcing elements come between thebarrier material and the surface of a shelf (at least at the corners ofthe sterilization tray), an increase in the basis weight of the combinedcomponents (i.e., the barrier material basis weight is constant andreinforcing element basis weight increases) results in a decrease infailure rates that compares favorably to a barrier material having acorresponding basis weight.

This is interpreted as providing a sterilization assembly in which thebasis weight of the barrier panel may be reduced or at least held to alow level while generating a profile of resistance to pressure cuts andpressure holes that was previously provided only by increasing the basisweight of the entire sterilization wrap material.

EXAMPLES

Aspects of the disposable flexible multi-panel sterilization assemblywere evaluated in the following examples.

Peel Test Procedure:

The resistance to peel force provided by the panel attachment means ofthe disposable flexible multi-panel sterilization assembly was evaluatedutilizing the following peel test procedure:

1.2 This test is intended to determine the “Z” direction peel strength(bond strength) required to separate two barrier panels that have beenoverlapped and joined together utilizing panel attachment means.1.3.1 If the panel attachment means are double-sided tape or a hook &loop-type fastening system or the like configured as shown in FIG. 8Aand FIG. 9A, two approximately 254 by 152.4 mm (10 by 6 inch) barrierpanel specimens are overlaid to sandwich a 101.6 by 25.4 mm (4 by 1inch) specimen of a panel attachment means that is positioned at thecenter (i.e., away from the edges) of the overlaid barrier panels.During the engagement of the panel attachment means, a roller is rolledover the test specimen through three cycles in the direction of the“length” of the sample. The roller device weighs 4.5 pounds and includesa rubber coating around the roller. A suitable roller is part numberHR-100 available from Chemsultants International, a business having alocation in Mentor, Ohio. Adjacent ends of the overlaid barrier panels(i.e., the two ends on the same side edge of the overlaid barrier panel)are then respectively clamped into the two opposing grips of a tensiletesting machine. Each end of the grip should be a distance of at leastabout 13 to 19 mm (0.5 to 0.75 inches) away from the panel attachmentmeans joining the two overlaid barrier panels. The average load neededto completely separate the barrier panels as the grips move away fromeach other is determined. This is the bond strength of the specimen.Results are expressed in units of grams-force; higher numbers indicate astronger, better bonded fabric.1.3.2 If the panel attachment means is a fastener extending outward fromor near a side of the barrier panel as shown in FIGS. 6, 7A and 7B, thedistal end or portion measuring 101.6 by 25.4 mm (4 by 1 inch) of afastener specimen (i.e., the end or portion that is unconnected to thebarrier panel as shows in FIGS. 6, 7A and 7B) is joined to a barrierpanel specimen. The proximal end or portion of the fastener (i.e., theend or portion that is pre-connected with the barrier panel as shown inFIGS. 6, 7A and 7B) is not joined. During the engagement of the panelattachment means, a roller is rolled over the test specimen throughthree cycles in the direction of the “length” of the sample. The rollerdevice weighs 4.5 pounds and includes a rubber coating around theroller. A suitable roller is part number HR-100 available fromChemsultants International, a business having a location in Mentor,Ohio. The distal end/portion of the fastener specimen is manuallyseparated from the barrier panel specimen for a distance of about 13 to19 mm (0.5 to 0.75 inches) along the length of the specimen. Themanually separated portion of the barrier panel specimen is then clampedinto a grip of a tensile testing machine and the manually separatedportion of the fastener specimen is then clamped into the other grip ofa tensile testing machine. The average load needed to completelyseparate the component layers of the fastener from the barrier panel asthe grips move away from each other is determined. This is the bondstrength of the specimen. Results are expressed in units of grams-force;higher numbers indicate a stronger, better bonded fabric.

1.4 Definitions

1.4.1 average load: Average of the peaks collected in the specified peelregion; i.e., between 25 and 178 millimeters.1.4.2 delamination: The separation of the layers of material due to afailure of the attachment mechanism. Attachment strength is the tensileforce required to separate barrier panels joined by panel attachmentmeans under specified conditions.1.4.3 Z-direction: Orientation perpendicular or normal to the plane ofthe material (i.e., the barrier panel).1.5 This method references MTS TestWorks® for Windows software.2.1 Verify the appropriate load cell is in the tensile tester. For loadcell conditioning (warm up), refer to the manufacturer's specifications.2.2 Ensure the appropriate grips are installed in the tensile tester.Ensure the grips and grip faces are free of build-up and the grip facesare free from dents or other damage.2.3 Ensure the air pressure to operate the grips is not set beyond themanufacturer's maximum loading specifications.2.4 Turn on the computer and then follow the software menu selection.2.5 Follow the instructions for calibrating the load cell for thetensile tester being used.2.6 Verify the tensile tester parameters meet the followingspecifications:

Crosshead Speed 305 ± 10 mm/minute (12 ± 0.4 inch) Gage Length 25.4 ± 1mm (1 ± 0.04 inch) Load Units Grams-force Full-Scale Load 10-pound loadcell Test Result Average load Start Measurement 25.4 ± 1 mm (1 ± 0.04inch) End Measurement 177.8 ± 1 mm (7 ± 0.04 inch) Endpoint 21.6 cm (8.5inches)3.1 Cut a 4 inch by 1 inch specimen of the panel attachments and proceedaccording to Step 1.3.1 or Step 1.3.2. Specimens should be handledminimally and be free of folds, wrinkles, or creases.4.1 Place the specimens in the grips according to Step 1.3.1 or 1.3.2.4.1.1 Mount the free end of one specimen into one grip and the free endof the other specimen into the other grip such that the bonded juncturesof the specimens are centered and there is no slack. Do not clamp thespecimens at an angle.4.2 Start the crosshead.4.3 Run the test until the specimens have completely separated (i.e.,delaminated). Do not push the return button or otherwise stop the testuntil the specimen has been completely pulled apart.4.4 Record the average load in grams-force.4.5 Remove the specimens.4.6 Repeat for the remaining specimens.5.1 Report the average load to the nearest 0.1 gram-force for eachindividual test of specimens.5.2 Calculate the average for all the specimens and report this as thesample value.

6.1 Tensile Tester

Constant-Rate-of-Extension (CRE) tensile tester with a computer-baseddata acquisition and frame control system

6.2 Load Cell

Choose the appropriate type for the tensile tester being used. Use aload cell in which the majority of the peak load results fall between 10and 90% of the capacity of the load cell. Obtain 6.1-6.2 from InstronCorporation, Canton, Mass. 02021, OR MTS Systems Corporation, EdenPrairie, Minn. 55344-2290.

6.3 Load Cell Adapter

15.9 mm upper—if needed.

6.4 Universal Joint

6.4.1 Optional: Sintech small load cellswivel

1/4-28 UNC male stud one side, 1/4-28UNC female thread opposite side,rated for 75 lbs.

6.4.2 Optional: Sintech universal load cellswivel

1/4-28 UNC male stud one side, 12.7 mm (0.50 inch) female socket otherside, rated for 300 lbs

6.4.3 Optional: Synergy load cell adapterswivel

15.88 mm (0.625 inch) male socket to 12.7 mm (0.50 inch) female socket,rated for 300 lbs.

6.6 Computer Data Acquisition and Control System for Tensile Tester

Example: MTS TestWorks® for Windows, or equivalent.

6.7 Test Macro

For use with MTS TestWorks® forWindows software version 4.0 OR InstronBluehill software;

6.8 Grips and Faces

Pneumatic

6.8.1 Top and Bottom Grips

Side-action, manual air switch; example: Instron Corporation part number2712-003, or equivalent AND

6.8.1.1 Grip Faces

25.4 by 76.2 millimeter (1 by 3 inch) faces, rubberized, top and bottom;example: Instron Corporation part number 2702-035, or equivalent OR

6.8.2.1 Standard Capacity Grips and Faces

Top and bottom—use standard capacity grips and faces combinationdesigned for a maximum load of 5000 grams. If the results approach thislimit, observe the material being tested. If slippage is noticed, usethe Instron grips and faces that have a 90.7-kg maximum load rating.

7.2 Laboratory conditions: Maintain a controlled testing environment of23±2° C. and 50±5% relative humidity.

Shear Test Procedure:

The resistance to shear force provided by the panel attachment means ofthe disposable flexible multi-panel sterilization assembly was evaluatedutilizing a test procedure substantially identical to the Peel TestProcedure set forth above, but with the following differences:

-   -   (i) A 50-pound load cell was used instead of a 10-pound load        cell.    -   (ii) In Step 1.3.1, the samples are oriented parallel to the        plane of travel of the grips and the opposite ends of the        overlaid barrier panels (i.e., the two ends on the opposite side        edges of the overlaid barrier panel) are clamped into each grip        of a tensile testing machine;    -   (iii) In Step 1.3.2, the distal end/portion of the fastener        specimen is manually separated from the barrier panel specimen        for a distance of about 13 to 19 mm (0.5 to 0.75 inches) along        the length of the specimen. The samples are oriented parallel to        the plane of travel of the grips. The manually separated portion        of the barrier panel specimen is then clamped into a grip of a        tensile testing machine and the manually separated portion of        the fastener specimen is then clamped into the other grip of a        tensile testing machine.    -   (iv) The Peak Load needed to completely separate the specimens        as the grips moved away from each other was measured instead of        the Average Load.

Example 1 Time and Motion Study

Test Subject Selection and Testing Sequence

A random population of 57 individuals with no or minimum healthcareexperience were selected for this study. These individuals were randomlyassigned to one of the two wraps for testing of the training andwrapping/unwrapping. The pre-requisite for their selection was limitedto not having any prior experience in a hospital's central sterilizationdepartment. The reason for this pre-requisite is that people withcentral sterilization experience may have already been exposed to theuse of surgical wraps and therefore would not be acceptable for testingrelated to training.

With regards to the testing sequence the first test was for thetime/ease of training. Once an individual was trained and consideredproficient at the use of one of the two surgical wraps that personbecame eligible for testing of the wrapping/unwrapping.

Training Test—Time Required to Learn Wrap Procedure

This training test was directed to the learning curve and timerequirements for a subject to be trained and to become proficient inwrapping and unwrapping one type of sterilization wrap.

The test to gauge time requirements for training an individual inwrapping began with a proficient trainer providing an overviewdemonstration of the wrap and the various types of equipment involved.He or she then provided a detailed, step-by-step demo of how the wrapwas used in practice to the test subject and answered any questions. Thenext step involved one last demonstration of wrapping and unwrapping atray straight through before handing off the session to the testsubject. The test subject continued attempting to successfully wrap andunwrap a tray with supervision and feedback. For every mistake made, asoutlined by the trainer, the test subject started the process over againfrom the beginning. Trainers provided guidance and coaching until a testsubject could successfully wrap a surgical tray five times sequentiallywithout any errors, missed steps, and/or feedback from his or hertrainer. This point marked the end of the test. Once a subject coulddemonstrate his or her ability and proficiency to successfully wraptrays, they were deemed a “proficient” test subject.

As mentioned above each test subject was trained on one type of wrap toeliminate any advantage he or she may have gained from previousexperience of using the other type of wrap. This also maintainedindependence between the two sample sets. Finally, a particular wrap wasnot used for more than three attempts during training. KimGuard®One-Step® wraps were flipped for a change in orientation after everyattempt and Multi-panel sterilization assemblies had release linersreapplied after every attempt.

Wrap and Unwrap Time

In order to test the wrap time, a pool of proficient subjects inwrapping trays with both the multi-panel sterilization assembly andKimGuard® One-Step® wrap was selected. As previously mentioned thesesubjects were identified during the training testing.

During wrap and unwrap time testing, the subjects were required tocontinuously wrap and unwrap a single size surgical tray with thefollowing approximate dimensions: length=20 inches, width=10.5 inchesand height=3.5 inches (the most common tray size used in hospitals).Wraps were discarded after each use (wrap and unwrap) to prevent testersfrom taking advantage of placement marks that could be created in thewrap after it was used. This ensured independence between the tests. Fortiming purposes the start of the wrapping process was when the wrap wasfully opened on top of the wrapping table, and the tester was holdingthe surgical tray in his or her hands. The end of the wrapping processwas when the tray was fully wrapped and taped, and the tester steppedback from the wrapping table. On the other hand, the start of theunwrapping process was when the tester first touched the wrap to unwrapthe tray, and the end when the tray was fully exposed on top of the openwrap and the tester stepped back from the wrapping table.

If during the wrapping or unwrapping process the subject did not followthe standard processes, the sample was not considered valid and the testrepeated.

Statistical Analysis Methodology

In designing the statistical analysis for each one of the two tests, itwas assumed the time it takes to wrap and unwrap and train personnel forboth wraps were independent and normally distributed. The approach takento analyze each of the two tests was to define a 95% confidence intervalon the difference between the means of labor time requirements for eachwrap. The confidence interval indicated if there was a statisticaldifference between the two mean times for each one of the two test, andif there was one, it determined what that difference was.

For each of the two tests, the mean time it takes to wrap/unwrap ortrain personnel using the KimGuard@ One-Step® wrap was denoted μ₁ andthe mean time it takes using the multi-panel sterilization assembly wasdenoted as μ₂. The variances were denoted σ₁ ² and σ₂ ² respectively.For this study, both the means and variances were unknown.

For each one of the two tests, random and independent time and motionstudies of sample size n₁ and n₂ were taken for the KimGuard® One-Step®wrap and multi-panel sterilization assembly respectively. Sample meantimes were denoted as xbar₁ and xbar₂, and sample variances as s₁ ² ands₂ ². To construct a 95% confidence interval on μ₁−μ₂ a pooled estimatorwas first calculated as follows:

S _(p) ²=[(n ₁−1)s ₁ ²+(n ₂−1)s ₂ ²]/(n ₁ +n ₂−2)

Then, a 95%, 100(1−α), two-sided confidence interval on μ₁−μ₂ wasdetermined utilizing the t statistic and distribution with degrees offreedom of n₁+n₂−2, and the following theorem:

xbar₁ −xbar₂ −t _(α/2,n1+n2−2) ×s _(p)×[(1/n ₁)+(1/n ₂)]^(0.5)≦μ₁−μ₂≦xbar₁ −xbar₂ −t _(α/2,n1+n2−2) ×s _(p)×[(1/n ₁)+(1/n ₂)]^(0.5)

The range, difference between means, obtained from this analysisstatistically validated the differences between the labor timerequirements for each one of the two tests stated above.

Sample Size Determination

Sample sizes for the two tests during the time and motion testing wasdetermined based on analyzing initial estimates of specified errorbetween population and sample means, standard deviations of theindependent sets of samples, and initial confidence intervalrequirements. From this initial analysis, appropriate sample sizes weredetermined utilizing the following statistical theorem:

n=[(Z _(α/2)σ)/e] ²

n=appropriate sample size

z=test statistic under the null hypothesis that can be approximated by anormal distribution

α=required confidence level, e.g. 95%

σ=estimated standard deviation of sample sets

e=specified error: |xbar−μ|

The α and e values control the level of precision required for theestimated mean labor time required by each wrap in each of the twotests. A 95% confidence level (α) and a ±10% error (e), were the minimumacceptable values for the sample size precision controls used in all ofthe tests.

Wrapping and Unwrapping Standard Procedures KimGuard® One-Step® WrappingStandard Procedures

This procedure is generally illustrated in FIGS. 4A to 4E.

Step 1—Lay Wrapper on Table Step 2—Position Instrument Tray Step 3—FoldBottom Over to Completely Cover Tray Step 4—Check to Make Sure Cornersare Covered Step 5—Fold Handle Back

Step 6—Hold Handle in Place with Elbow

Step 7—Gather One Side Step 8—Fold Side Step 9—Fold Side Handle Back

Step 10—Hold Handle with Elbow and Gather Opposite Side

Step 11—Fold Side Step 12—Fold Opposite Side Handle Back

Step 13—Hold Handles with Elbows and Grab Top

Step 14—Gather Top to Create Final Flap Step 15—Bring Final Flap OverPackage Step 16—Spread Sides of Top so Whole Package is Covered Step17—Tuck to Create Opening Handle

Step 18—Secure with Tape Step 1 (first piece of tape across tucked finalflap)Step 19—Secure with Tape Step 2 (second piece of tape across tuckedfinal flap)Step 20—Secure with Tape Step 3 across entire width of package to sealeach side

Done KimGuard® One-Step® Unwrapping Standard Procedures

Step 1—Break Long Tape on Each Side Step 1 &2 (i.e., break tape appliedin Wrapping Step 20 at each side of package)Step 2—Break Tape Step 3 (i.e., break tape applied in Wrapping Step 18across tucked final flap)Step 3—Break Tape Step 4 (i.e., break tape applied in Wrapping Step 19across tucked final flap)Step 4—Grab Opening Handle (i.e., handle created in Wrapping Step 17)

Step 5—Pull Handle Towards You Step 6—Unfold Top Layer Away From You

Step 7—Grab Side Handle and Pull to the Side (i.e., handle created inWrapping Step 12)Step 8—Grab Other Side Handle and Pull to Side (i.e., handle created inWrapping Step 9)Step 9—Grab Final Fold Handle (i.e., handle created in Wrapping Step 5)

Step 10—Pull to Open Final Fold Done Multi-Panel Sterilization AssemblyWrapping Standard Procedures

This procedure is generally illustrated in FIGS. 9A to 9E.

Step 1—Lay Multi-Panel Sterilization Assembly on Table Step 2—PositionInstrument Tray Step 3—Fold Bottom Over to Completely Cover Tray

Step 4—Remove Release Liner from one Side Exposing Adhesive onPre-Attached Tape (i.e., Panel Attachment Means)

Step 5—Gather One Side Step 6—Fold Side & Secure Pre-Attached Tape(i.e., Panel Attachment Means)

Step 7—Remove Release Liner from Other Side Exposing Adhesive onPre-Attached Tape (i.e., Panel Attachment Means)

Step 8—Gather Opposite Side Step 9—Fold Side & Secure Pre-Attached Tape(i.e., Panel Attachment Means) Step 10—Gather Final Flap at Top (i.e.,Fold Protection Panel) Step 11—Bring Final Flap Over Package Step12—Fold Edge Under Final Flap

Step 13—Secure with Tape Step 1 (first piece of tape across tucked finalflap)Step 14—Secure with Tape Step 2 (second piece of tape across tuckedfinal flap)

Done Multi-Panel Sterilization Assembly Unwrapping Standard Procedures

Step 1—Break Tape Step 1 (i.e., break tape applied in Wrapping Step 13across tucked final flap)Step 2—Break Tape Step 2 (i.e., break tape applied in Wrapping Step 14across tucked final flap)

Step 3—Unfold Top Layer (i.e., Fold Protection Panel) Away From You Step4—Grab Sides Using Two Hands Step 5—Peel Tape (i.e., Panel AttachmentMeans) to Unfold Sides Step 6—Grab Opening Handle (i.e., Pull Tab) atLabel Step 7—Lift Label Up Step 8—Pull Towards You Done Test Results

Wrap and Unwrap Time

The following data summarizes the statistical results of testing forwrapping and unwrapping time with the KimGuard® One-Step® wrap andmulti-panel sterilization assembly.

TABLE 1A Wrapping Time Multi-Panel KimGuard ® One-Step ® SterilizationAssembly Wrapping Procedure Wrapping Procedure Sample Size 82 95Collected Sample Mean 1 min 43 sec 32 sec Sample Standard 36 sec  7 secDeviation Specified Error   10.3 sec (10%)    3.2 sec (10%) MinimumSample 80 31 Size Required

The statistical difference between the mean wrapping times for theKimGuard® One-Step® wrap and the multi-panel sterilization assembly wasdetermined from the data summarized above. With a 95% confidence level,the actual difference between the labor time requirements for the twowraps falls in the following range: 1.06 minutes≦μ₁−μ₂≦1.3 minutes.Because this range does not include zero, it can be inferred thatwrapping labor requirements for the KimGuard® One-Step® wrap arestatistically greater than those for the multi-panel sterilizationassembly.

TABLE 1B Unwrapping Time Multi-Panel KimGuard ® One-Step ® SterilizationAssembly Unwrapping Procedure Unwrapping Procedure Sample Size 82 95Collected Sample Mean 15.8 sec  5.6 sec Sample Standard 3.0 sec 1.5 secDeviation Specified Error    1.6 sec (10%)    0.6 sec (10%) MinimumSample 15 29 Size Required

Statistical Results

The statistical difference between the mean unwrapping times for theKimGuard® One-Step® wrap and multi-panel sterilization assembly wasdetermined from the data set collected above. With a 95% confidencelevel, the actual difference between the labor time requirements for thetwo wraps falls in the following range: 9.5 seconds≦μ₁−μ₂≦10.9 seconds.Because this range does not include zero, it can be inferred thatunwrapping labor requirements for the KimGuard® One-Step® wrap arestatistically greater than those for the multi-panel sterilizationassembly.

Training Test—Time Required to Learn Wrap Procedure

The following data summarizes the statistical results of testing fortraining time with the KimGuard® One-Step® wrap and multi-panelsterilization assembly.

TABLE 1C Training Time Multi-Panel Sterilization KimGuard ® One-Step ®Assembly Unwrapping Unwrapping Procedure Procedure Sample Size 21 36Collected Sample Mean 42.4 min  20.8 min  Sample Standard 8.4 min 6.1min Deviation Specified Error    4.3 min (10%)    2.1 min (10%) MinimumSample 16 33 Size Required

Statistical Results

The statistical difference between the mean training times for theKimGuard® One-Step® wrap and multi-panel sterilization assembly wasdetermined from the data set collected above. With a 95% confidencelevel, the actual difference between the training labor timerequirements for the two wraps falls in the following range: 17.7minutes≦μ₁−μ₂≦25.5 minutes. Because this range does not include zero, itcan be inferred that training labor requirements for the KimGuard®One-Step® wrap are statistically greater than those for the multi-panelsterilization assembly.

CONCLUSIONS Wrap and Unwrap Time Wrapping

With an average wrapping time of 1 minute 43 seconds for the KimGuard®One-Step® wrap and an average wrapping time of 32 seconds for theMulti-panel sterilization assembly, test results establish an average68% reduction in time when comparing the two wraps. This observedreduction in time is a result of various factors. Wrapping surgicaltrays using the multi-panel sterilization assembly provides a moresimple and intuitive technique for its user compared to its counterpart.There are fewer, less complex steps as well as fewer touches required towrap a tray. The multi-panel sterilization assembly features referencelines (i.e., pre-determined fold lines) for initial accurate placementof trays, pre-attached release liner adhesives and less material tohandle. Furthermore, sealing a wrapped tray with tape using themulti-panel sterilization assembly takes on average 6.2 seconds comparedto the 18.2 seconds required on average for the KimGuard® One-Step®wrap. This is due to not having to seal the top of the tray (across themulti-panel sterilization assembly) with tape.

If the final taping process is excluded from the wrapping process (SeeWrapping Steps 18, 19 and 20 for the KimGuard® One-Step® wrap andWrapping Steps 13 and 14 for the Smart-Fold package) the averagewrapping time is 1 minute 25 seconds for the KimGuard® One-Step® wrapand 26 seconds for the multi-panel sterilization assembly. Thatrepresents an average 69% reduction in wrapping time.

Unwrapping

The KimGuard® One-Step® wrap, on average, takes 15.8 seconds to unwrapin comparison to the multi-panel sterilization assembly, which takes 5.6seconds. This drop in unwrapping time represents an average 64%reduction in time. This reduction is the result of less sealing taperequired to be broken for the multi-panel sterilization assembly (i.e.two breaking points rather than four from KimGuard® One-Step® wrap) anda less complex procedure that allows simultaneous movements withoutdirectly coming into contact with the surgical tray.

Training—Time Required to Learn Wrap Procedure

Training end users on the proper standard operating procedures to wrapand unwrap trays requires, on average, 42.4 minutes for the KimGuard®One-Step® wrap and 20.8 minutes for the Multi-panel sterilizationassembly. The reason for this 51% decrease in time similarly reflectsthe points outlined in the wrapping and unwrapping hypothesis discussedabove. The more intuitive, less complex, fewer steps, and ergonomicconfiguration effectively allowed users to more quickly learn anddemonstrate proficiency in proper wrapping and unwrapping techniques forthe multi-panel sterilization assembly compared to the KimGuard®One-Step® wrap.

Example 2

An exemplary disposable flexible multi-panel sterilization assembly 100was constructed to have five sides or edges. This geometry is generallyas illustrated in FIG. 6. A second edge 122 of the barrier panel 102 ofthe multi-panel sterilization assembly is approximately 36 inches inlength. A first edge 120 and a third edge 124 of the barrier panel 102are perpendicular to the second edge 122 and are each approximately 35inches long. A first edge 146 and a second edge 148 of the foldprotection panel 108 are each approximately 19 inches long and cometogether at an obtuse angle (not necessarily as depicted in FIG. 6). Thefirst edge 146 and second edge 148 of the fold protection panel 108 aredirectly across from the 36 inch long edge bottom edge 122 of thebarrier panel 102. This design covers a typical sterilization trayhaving about 700 square inches of surface area for sterile processingwhen the sterilization tray is placed in the content receiving region130 and the bottom edge 122 is folded up and over to cover the top ofthe tray.

The panel attachment means 106 which may be in the form of twopre-attached tape tabs are used to pull the first edge 120 and thirdedge 124 of the barrier panel 102 over the top of the tray and then tapethe edges down onto the back of the sheet already folded over the top ofthe tray. The use of these tabs enables the design to use a much shorterlength while confidently taping down the side folds when preparing thetray for sterilization. Furthermore, the use of these tabs willfacilitate the wrapping process making it both easier and faster toprepare a tray for sterile processing. After folding over and tapingdown the sides of the wrap, the top of the wrap is then folded over thetop of the tray and the preparer of the tray can then tuck the topcorner of the wrap back under and the out with a z-fold creating a pullpoint on the wrap for aseptic opening in the operating room.

The surface area of this design is just 1260 square inches meaning thatjust 1.8 square inches of barrier panel is needed to cover each squareinch of tray surface. In addition to a shaped design reducing materialneeded to wrap an instrument tray, the design provide two layers ofsterilization fabric (i.e., barrier panel) only where it is necessary tocover each square inch of the surface area of an instrument tray. Twolayers are generally the configuration needed to provide a sufficientmicrobial barrier. Therefore, the additional surface area of materialused to wrap a sterilization tray need not serve as a microbial barrier.As a result, it can simply be a single layer of material—that is, a foldprotection panel.

Example 3

Conventional wrapping systems sequentially utilize single plysterilization wrap or utilizing a two-ply sterilization wrap (e.g.,KimGuard® One-Step® sterilization wrap) to fold around a standard tray.It is generally thought that excess material that overlaps and providesmultiple folds, plies or layers at the top or upper region of thewrapped package is needed to maintain a sterile barrier.

This example illustrates the reduction in the number of plies, layers orfolds of material on the top or upper region of a standard tray whenwrapped utilizing the multi-panel sterilization assembly. Compared to astandard tray that is wrapped using a conventional wrapping system, themulti-panel sterilization assembly provides far fewer plies, layers orfolds on the top or upper region while maintaining the tortuous pathrequirements generally thought necessary to provide a sterile barrier.This example also describes a method of sectioning a wrapped packagecontaining a standard article (i.e., a sterilization tray havingapproximate dimensions of length=20 inches (˜510 mm), width=10.5 inches(˜270 mm) and height=3.5 inches (˜88 mm) that allows for differences inthe wrapped configurations to be measured.

Conventional sterilization wrapping uses two (2) similarly sizedsuperposed sheets to wrap articles, via either the envelope fold method(See FIGS. 4A to 4E) or the square fold method (See FIGS. 5A to 5E).Such superposed sheets are sheet plies 14 and 16 of FIG. 1. Suitablebarrier materials are single ply sterilization wraps and Table 2 listsexamples and their characteristic basis weights in terms of ounces persquare yard and Frazier permeability in terms of CFM at a pressuredifferential of 125 Pa as determined from 3 inch diameter specimens inaccordance with ISO 9237:1995 (measured with an automated airpermeability machine using a 38 cm² head at a test pressure of 125 Pa, -exemplary air permeability machine is TEXTEST FX 3300 available fromTEXTEST AG, Switzerland). These sterilization wraps are currently soldby Kimberly-Clark Corporation (Dallas, Tex.).

TABLE 2 Single Ply Frazier permeability Sterilization Standard WrapsBasis Weight Average* Deviations, +/− KC100 1.05 osy (~35 gsm) 37.841.0469 KC200 1.20 osy (~40 gsm) 66.44 3.13234 KC300 1.40 osy (~47 gsm)52.68 5.552537 KC400 1.85 osy (~62 gsm) 37.13 1.120565 KC500 2.05 osy(~68 gsm) 30.91 0.792254 KC600 2.57 osy (~86 gsm) 25.99 1.395588*Average values are based on 10 specimens for each sample.

These conventional wraps create large expanses of overlapping materialsthat restrict air flow permeability (Permeability) in addition to theinherent restriction of the unfolded sterilization wraps themselves. Theoverlapping folds corresponding add weight through accumulated stackedplies/layers in excess of that necessary to ensure adequate barrierprotection and establishment of the desired tortuous path. Theseoverlaps tend to concentrate in specific regions dictated by the foldingpatterns used to wrap articles. In wrapping box-like articles, e.g.surgical trays, the wrapping mimics the box-like shape and presentsdistinct Top, Bottom, and Side Strip regions as definable specificregions. FIG. 19 illustrates the Top region 402, the Bottom region 404,and Side Strip region 406.

When the invention uses barrier panels composed of two (2) layers orplies, which is the number of layers or plies commonly used conventionalwrap systems, the present invention when configured around the trayconsistently reduces in the Top region 402 (i) the number of stackedplies, (ii) the amount of material, and (iii) the resistance to air flow(and hence sterilant gas such as, for example, steam or ethylene oxide)as compared to conventional sterilization wrap systems. These reductionsare demonstrated by sectioning the wrappings from around wrapped traysinto separated Top, Bottom and Side Strip regions and sampling theseregions for subsequent measurements as indicated in FIG. 25 to obtainprofile representations of air flow permeability, weight and the maximumnumber of stacked plies. From such representations, the advantages ofthe invention in reducing the number or amount of folds and the amountof material needed to wrap an article, even with the inclusion of anyreinforcement elements, are connected to quantifiable measurements thatinclude Frazier Permeability (Permeability, CFM), weight per 3-inchdiameter specimen area (Wgt, gms), and a count of the maximum number ofstacked plies in the 3-inch diameter specimen area (Plies). Thesemeasurements made in Top, Bottom and Side Strip regions are subsequentlypresented via FIGS. 26-42 and Tables 5-19 for the multi-panelsterilization assembly of the present invention and for conventionalsterilization wrap systems that use the envelope folding method. Twosheets, layers or plies of barrier material are utilized for theconventional sterilization wrap and corresponding constructions are usedin the barrier panels of the present invention to provide a more directcomparison.

Conventional sterilization wrap is folded about a conventionalsterilization tray utilizing the envelope fold method rather than thesquare fold pattern in making the comparison to the multi-panelsterilization assembly through quantitative measurement for two reasons:(i) the envelope fold pattern is much more prevalent in use; and (ii)the square fold pattern creates overlaps in material that areexplainable and quantifiable without the need of measurements in orderto compare to the invention (the envelope fold pattern creates morecomplex overlaps). As is subsequently shown and discussed, the Topregion of the wrapping around an article is the region wheredistinctions among the wrapping systems are greatest. The Bottom regionhas the least distinctions, and those of the Side Strip regions are lessclear. Because articles are typically constructed to emit and ventsterilant gases through the Top and Bottom regions, and since the SideStrip regions tend to be solid supporting walls, the distinctions amongwrapping systems in the Top region are of particular relevance.Moreover, the Top region is where the edges of conventionalsterilization wrap are gathered/folded together to provide potentialopenings or pathways through the barrier material that areconventionally believed to be overcome by employing excess, overlappingwrap material.

Before addressing the amount/number of overlapping plies or layers ofmaterial for the multi-panel sterilization assembly of the presentinvention and for conventional wrapping systems utilizing the envelopefold method, the following discussion will address the amount/number ofoverlapping plies or layers of material for conventional wrappingsystems utilizing the square fold method. Referring generally to FIGS.5A-E, the minimum amount/number of overlapping plies or layers ofmaterial resulting from wrapping a conventional sterilization tray orother box-like article using the square fold method is determined as theminimum number of stacked plies in the Top region of the wrappedarticle. For each conventional sheet of sterilization wrap used in thesquare fold method:

-   -   one (1) ply results from a first fold of the bottom end 66 over        an article (62),    -   at least one (1) ply results from folding the top end 70 over        the article, and    -   at least three (3) plies result from folding the left side end        72, which has ply contributions from the bottom and top end        folds, over the article.

Thus, each separate sheet of sterilization wrap folded around a box-likearticle using the square fold method contributes at least five (5)stacked plies in the Top region 402 (see FIG. 19). This minimum count ofstacked plies excludes any back-folding of the bottom, top and left sideends 66, 70, 72, as conventionally done and also excludes anycontributions from folding over the right side end 74 that completes thewrapping. This minimum of five (5) stacked plies per separate sheet ofsterilization wrap is doubled to ten (10) plies when two (2) sheets ofsterilization wrap are used—either sequentially or simultaneously. For agiven construction of a sheet of sterilization wrap, the minimum weightand the air permeability through the stacked plies can be determinedfrom the properties of the sheet of sterilization wrap (e.g., those forbasis weight and Frazier permeability) given in Tables 2 and 3, and fromthe number of stacked plies or layers.

As is subsequently shown, this minimum ten (10) stacked plies/layers inthe Top region for wrapping with two (2) sheet of sterilization wrapusing the square fold method exceeds those of the invention having abarrier panel composed of two (2) layers or plies and a fold protectionpanel composed of one (1) or even two (2) layers or plies. The squarefold wrapping method or pattern provides a number of stacked plies inthe Bottom region that are the same as those for the envelope foldwrapping method or pattern, and which are also similar to the numberprovided in the Bottom region 404 (see FIG. 19) by the multi-panelsterilization assembly. With respect to the Side Strip region 406 (seeFIG. 19), the overlap of conventional sterilization wrap material in asquare fold wrapped article is expected to yield similar ply stacking asan envelope fold wrapped article and an article wrapped using themulti-panel sterilization assembly given the nature of all these foldingsystems to fold for aseptic unfolding after sterilization from the Topregion.

The embodiments of the multi-panel sterilization assembly of the presentinvention previously discussed for FIG. 8A, FIGS. 9A-E, and FIG. 13 areused to represent the quantification of the wrapping per the inventionand specific representative embodiments are illustrated in FIG. 21 withthe fold protection panel 108 having one (1) ply and FIG. 22 with thefold protection panel 108 having two (2) plies. This example comparesthese embodiments with conventional sterilization wrap systems thatutilize the envelope fold pattern or technique and which are illustratedin FIG. 14 and FIG. 16. Thus, in order to provide a direct comparison,the conventional sterilization wrap systems and the multi-panelsterilization assembly use two (2) layers, plies or sheets of material.Representative constructions of superposed sterilization wrap thatinvolving stacking two (2) plies of Sterilization Wrap of the typelisted in Table 2 yield Permeability values given in the following Table3:

TABLE 3 Barrier Panel Construction Frazier permeability (Stacking of 2plies Standard of Sterilization Wrap) Average* Deviations, +/− KC100 &KC200 31.37 1.725815 KC200 & KC200 29.77 1.879746 KC400 & KC400 18.571.301324 KC600 & KC400 16.6 0.957642 KC600 & KC400 12.89 0.35103*Average values are based on at least 10 specimens for each sample.

Sample wrappings for quantification proposes were made using themulti-panel sterilization assembly of the invention as shown in FIGS. 21and 22 and according to the conventional envelope fold systems as shownin FIGS. 14 and 16. These samples are identified in Table 4 for labelingin related tables and figures of graphs of Permeability, Weight, andPlies with respect to Position (e.g., Top, Bottom and Side Strip) andare subsequently described with respect to FIGS. 14-18 and 21, 22, and24. All samples of Table 4 wrapped around surgical trays withapproximate dimensions of 20 inches long×10.75 inches wide×3.5 inches(˜510 mm×˜270 mm×˜88 mm).

TABLE 4 Samples for Quantification Measurements Wrapping Barrier PanelPlies in Fold Reinforce- System Construction Protection ment Sample per:(per Table 3) Panel elements Hi Wgt Invention KC600 & KC400 1 Yes New1Lo Wgt Invention KC100 & KC200 1 Yes New1 Hi Wgt Invention KC600 & KC4002 Yes New2 Lo Wgt Invention KC100 & KC200 2 Yes New2 Hi Wgt envelopeKC600 & KC400 0 No ONE-STEP fold Lo Wgt envelope KC100 & KC200 0 NoONE-STEP fold Hi Wgt Seq envelope KC600 & KC400 0 No fold Lo Wgt Seqenvelope KC100 & KC200 0 No fold

“Hi Wgt” signifies superposed layers of KC600 and KC400. “Lo Wgt”signifies superposed layers of KC100 and KC 200.

Hi Wgt New1 and Lo Wgt New1 samples are representations of the two (2)layer barrier panel and single layer fold protection panel constructionillustrated in FIG. 21. Indicated in FIG. 21 are 2 reinforcing elementspositioned according to FIG. 10B and a pull tab. The wrapping of thesesamples around respective surgical trays followed the sequence shown inFIG. 9A-9E and a completed wrapping is illustrated in FIG. 24.

Hi Wgt New2 and Lo Wgt New2 samples are representations of the two (2)layer barrier panel and two (2) ply or layer fold protection panelconstruction illustrated in FIG. 22. Indicated in FIG. 22 are two (2)separate reinforcing elements positioned according to FIG. 10B and apull tab. Wrapping of these samples was the same as for the Hi and LoWgt New1 samples and a completed wrapping is illustrated in FIG. 24.

Hi Wgt ONE-STEP and Lo Wgt ONE-STEP samples are representations of thetwo (2) layer construction illustrated in FIG. 14 where the edges of thesuperposed sheets of conventional sterilization wrap align; anothersuitable construction for these ONE-STEP samples is shown in FIG. 1where the superposed aligned sheets of sterilization wrap are joinedtogether. No reinforcing elements or pull tab are present. The wrappingof these samples around respective surgical trays followed the sequenceshown in FIGS. 4A-4E and a completed wrapping is illustrated in FIG. 15.The letters “OS” may be used as an abbreviation for ONE-STEP withrespect to these samples.

Hi Wgt Seq and Lo Wgt Seq samples are representations of the two (2)layer construction illustrated in FIG. 16 where the separate sheets ofconventional sterilization wrap are not aligned but are offset withrespect to each other by approximately 45 degrees. No reinforcingelements or pull tab are present. To wrap a surgical tray, each sheet ofsterilization wrap sequentially folds around the tray according to thesequence shown in FIGS. 4A-4E. FIG. 17 illustrates the wrapping of thefirst sheet of sterilization wrap with the second sheet of sterilizationwrap yet to be wrapped around the surgical tray. FIG. 18 illustrates thecompleted wrapping of both barrier panels.

The completed wrappings for all samples, inclusive of the Hi Wgt and LoWgt New1 and New2 samples, form the specific fold over regions ofmaterials indicated by the labeling in FIG. 19 as Top 402, Bottom 404,Side Strip 406.

FIG. 14 illustrates a standard sterilization tray “T” (approximatelength=20 inches (˜510 mm), width=10.5 inches (˜270 mm) and height=3.5inches (˜88 mm)) and a sheet of bonded two-ply sterilization wrap (e.g.,KimGuard® One-Step® sterilization wrap) prior to wrapping. FIG. 15illustrates the sterilization tray after it has been wrapped inaccordance with the procedure illustrated in FIGS. 4A to 4E.

FIG. 16 illustrates a standard sterilization tray “T” (approximatelength=20 inches (˜510 mm), width=10.5 inches (˜270 mm) and height=3.5inches (˜88 mm)) and two sheets of single ply sterilization wrap priorto wrapping. FIG. 17 illustrates the sterilization tray after it hasbeen wrapped in the first sheet of single ply sterilization wrapaccordance with the procedure illustrated in FIGS. 4A to 4E. FIG. 18illustrates the sterilization tray after it has been sequentiallywrapped in the second sheet of single ply sterilization wrap accordancewith the procedure illustrated in FIGS. 4A to 4E.

FIG. 19 generally illustrates a standard sterilization tray “T”(approximate length=20 inches (˜510 mm), width=10.5 inches (˜270 mm) andheight=3.5 inches (˜88 mm)) that has been wrapped sequentially utilizingsingle ply sterilization wrap or wrapped utilizing a bonded two-plysterilization wrap (e.g., KimGuard® One-Step® sterilization wrap), bothin accordance with the procedure illustrated in FIGS. 4A to 4E, to forma package 400 having a top 402, a bottom 404 and sides 406.

FIG. 20 illustrates how the wrapped tray is divided into sections. Thetray is divided into five length rows (each length row beingapproximately 3.5 to 4 inches long) along its 20 inch length. The trayis also divided into three width rows (each width row beingapproximately 3.5 inches wide) and one height row that is approximately3.5 inches high. There is a 3×5 array for the top 402 of the wrappedtray and a separate 3×5 array for the bottom 404 of the wrapped tray.The front and back of the wrapped tray are divided into separate 1×5arrays, and each side is divided into separate 1×3 arrays.

The length rows are assigned a position number from 1 to 5 starting withposition 1 at the left side of the tray and running to position 5 at theright side of the tray. The width rows are assigned a position location(i.e., Front, Middle, and Back).

FIG. 21 illustrates a standard sterilization tray “T” (approximatelength=20 inches (˜510 mm), width=10.5 inches (˜270 mm) and height=3.5inches (˜88 mm)) and a multi-panel sterilization assembly of the presentinvention generally in accordance with FIG. 8A prior to wrapping. Itshould be noted that the barrier panel 102 has two plies of material andthe fold protection panel 108 has a single ply of material. FIG. 22illustrates a standard sterilization tray “T” (approximate length=20inches (˜510 mm), width=10.5 inches (˜270 mm) and height=3.5 inches (˜88mm)) and another configuration of the multi-panel sterilization assemblyof the present invention generally in accordance with FIG. 8A prior towrapping. It should be noted that the barrier panel 102 has two plies ofmaterial and the fold protection panel 108 also includes two plies ofmaterial. FIG. 24 illustrates the sterilization tray after it has beenwrapped in accordance with the procedure illustrated in FIGS. 9A to 9E.FIG. 23 illustrates the wrapped sterilization tray divided intosections. As illustrated previously in FIG. 20, there is a 3×5 array forthe top 402 of the wrapped tray and a separate 3×5 array for the bottom404 of the wrapped tray. The front and back of the wrapped tray aredivided into separate 1×5 arrays, and each side is divided into separate1×3 arrays.

The Top 402, the Bottom 404, and the Side 406 regions are shownseparated in FIG. 25. Such separation can be achieved by severing theregions apart using scissors or a sharp knife, but an exemplary methodcuts the regions apart with a cautery, such as the electrically poweredThermal Cautery Unit, Model 150, made by Geiger Medical Technologies(Monarch Beach, Calif.). Use of such an electrically powered cauteryfuses the edges of the severed material together so that each region402, 404, and 406 forms a unitary construction that simplifies cuttingout specimens for subsequent measurements without the need to bind thesevered edges with tape or other adhesive. From each separated region,specimens were cut that correspond to respective positions in the arraysusing a 3-inch circular die.

The following Tables 5 to 19 give measurements made for specimens thatare 3-inch (7.62 cm) in diameter and are taken from the Top, Bottom andSide Strip regions after sectioning. These measurements are presentedas:

-   -   averaged values of individual measurements for Permeability,        weight and ply count for two or three samples in each row        position, except as indicated by “*”. For example for the Hi Wgt        ONE-STEP sample in Table 9, the Front 1 value of 4.7 (CFM) is        the average of 3 specimens from 3 respective separate Top        samples. Typical standard deviations for these averaged values        were less than 15% of the averaged value. Sample labels in        Tables 5, 6, 8, 9, 12, and 13 that are followed by an “*” symbol        designate individual measurements from a single sample rather        than an average of measurements from two or three samples.    -   “Avg” sample values, e.g. Avg Hi Wgt ONE-STEP, Avg Hi Wgt New1,        and are the averages among the respective Front, Middle and Back        row averaged values; for example in Table 9 the Avg Hi Wgt        ONE-STEP Position 1 value of 5.1 (CFM) is the average of the        Front's 4.7, the Middle's 5.4 and the Back's 5.2 averaged        values. For the Top and Bottom regions such reporting does not        alter the relative directional change with respect to adjacent        positions established by the average values reported in each        row. This retention of direction changes is shown by comparing        FIG. 26 to FIG. 27 and FIG. 28 to FIG. 29. FIG. 26 graphs the        averaged values for each row (Front, Middle, back) for each        sample for the Bottom region of a sectioned wrapping and FIG. 27        graphs the same data but expressed as the “Avg” sample values;        FIG. 28 similarly graphs the averaged values for each row        (Front, Middle, back) for each sample for the Top region of a        sectioned wrapping and FIG. 29 graphs the same data expressed as        the “Avg” sample values. Reporting the data as “Avg' sample        values visually clarifies the distinctions of the invention from        the other wrapping systems.

TABLE 5 Maximum Plies in Bottom region of wrappings Position: 1 2 3 4 5Avg Hi Wgt ONE-STEP 2 2 2 2 2 Avg Hi Wgt Seq 2 2 2 2 2 Hi Wgt New2 Front2.5 1 1 1.5 3 Hi Wgt New2 Middle 3 2 2 2 2.5 Hi Wgt New2 Back 3 2 1.5 23 Avg Hi Wgt New2 2.8 1.7 1.5 1.8 2.8 Hi Wgt New1* Front 2 1 1 1 2 HiWgt New1* Middle 2 1 1 1 2 Hi Wgt New1* Back 2 1 1 1 2 Avg Hi Wgt New1 21 1 1 2

TABLE 6 Maximum Plies in Top region of wrappings Position: 1 2 3 4 5 HiWgt ONE-STEP Front 12.3 12.3 20.7 15.3 14.7 Hi Wgt ONE-STEP Middle 1215.7 26.3 20.7 13.3 Hi Wgt ONE-STEP Back 11 12.7 15.7 13.3 11.3 Avg HiWgt ONE-STEP 11.8 13.6 20.9 16.4 13.1 Hi Wgt Seq Front 14.7 13.7 23.715.7 16 Hi Wgt Seq Middle 12.7 16 23 19.7 14 Hi Wgt Seq Back 12 12.717.3 14 12 Avg Hi Wgt Seq 13.1 14.1 21.3 16.4 14 Hi Wgt New2 Front 11 85 4.5 15 Hi Wgt New2 Middle 11 9 5 6 12 Hi Wgt New2 Back 9 10 5.5 6 8.5Avg Hi Wgt New2 10.3 9 5.2 5.5 11.8 Hi Wgt New1* Front 9 3 4 4 9 Hi WgtNew1* Middle 7 6 4 4 9 Hi Wgt New1* Back 7 7 4 6 11 Avg Hi Wgt New1 7.75.3 4 4.7 9.7

TABLE 7 Maximum Plies in Top and Bottom regions of wrappings Position: 12 3 4 5 Lo Wgt ONE-STEP Front 15.3 21 22.7 19.7 15.7 Lo Wgt ONE-STEPMiddle 14.7 19 25.3 17.3 16.3 Lo Wgt ONE-STEP Back 14.7 14.3 21.7 1512.7 Avg Lo Wgt ONE-STEP 14.9 18.1 23.2 17.3 14.9 Lo Wgt Seq Front 18.319.7 27 24 16.7 Lo Wgt Seq Middle 21 28.3 33.7 21 11.7 Lo Wgt Seq Back18.3 18 23.3 13 14.7 Avg Lo Wgt Seq 19.2 22 28 19.3 14.3 Lo Wgt New2Front 18 13 7 6 16.5 Lo Wgt New2 Middle 13.5 13 6 7 15 Lo Wgt New2 Back12 8.5 7 9.5 13.5 Avg Lo Wgt New2 14.5 11.5 6.7 7.5 15 Lo Wgt New1 Front10 4 4 4 9 Lo Wgt New1 Middle 9 7.5 5 8 9.5 Lo Wgt New1 Back 10 9 6 711.5 Avg Lo Wgt New1 9.7 6.8 5 6.3 10 BOTTOM Lo Wgt New1 Front 3 2 2 2 3Lo Wgt New1 Middle 3 2 2 2 3 Lo Wgt New1 Back 3 2 2 2 3 Avg Lo Wgt New13 2 2 2 3 Lo Wgt New2 Front 3 2 2 2 2.5 Lo Wgt New2 Middle 3 2 2 2 3 LoWgt New2 Back 3 2 2 2 3 Avg Lo Wgt New2 3 2 2 2 2.8 Avg Lo Wgt OS & Seq2 2 2 2 2

TABLE 8 Permeability, CFM in BOTTOM region Position 1 2 3 4 5 Hi WgtONE-STEP Front 15.8 15.8 15.7 16.1 15.4 Hi Wgt ONE-STEP Middle 16.4 15.815.7 15.6 16.1 Hi Wgt ONE-STEP Back 15.8 16.2 15.6 15.9 16.1 Avg Hi WgtONE-STEP 16 15.9 15.7 15.9 15.9 Hi Wgt Seq Front 17.4 16.8 17.7 17.317.7 Hi Wgt Seq Middle 17 17.3 17.5 17.9 17.1 Hi Wgt Seq Back 16.9 17.717.7 17.6 16.3 Avg Hi Wgt Seq 17.1 17.3 17.7 17.6 17.0 Hi Wgt New2 Front13.9 14.8 15.0 15.65 15.3 Hi Wgt New2 Middle 13.8 15.3 14.8 15.7 16 HiWgt New2 Back 13.7 14.9 14.7 15.6 14.7 Avg Hi Wgt New2 13.8 15.0 14.815.7 15.3 Hi Wgt New1* Front 15.4 14.7 15.1 16 14 Hi Wgt New1* Middle14.2 15.5 14.9 15.4 14.5 Hi Wgt New1* Back 15.1 14.7 14.8 16.2 14 Avg HiWgt New1 14.9 15.0 14.9 15.9 14.2

TABLE 9 Permeability, CFM in TOP region Sample Position: 1 2 3 4 5 HiWgt ONE-STEP Front 4.7 4.9 6.2 4.9 4.2 Hi Wgt ONE-STEP Middle 5.4 5.35.0 5.1 5.8 Hi Wgt ONE-STEP Back 5.2 5.3 5.3 5.2 9.3 Avg Hi Wgt ONE-STEP5.1 5.2 5.5 5.1 6.4 Hi Wgt Seq Front 4.7 5.3 5.3 4.6 4.4 Hi Wgt SeqMiddle 5.0 4.7 4.7 5.0 5.5 Hi Wgt Seq Back 5.8 5.5 5.3 5.2 5.4 Avg HiWgt Seq 5.2 5.2 5.1 4.9 5.1 Hi Wgt New2 Front 6.8 8.6 9.9 17.5 9.2 HiWgt New2 Middle 4.8 8.8 7.3 8.0 5.2 Hi Wgt New2 Back 5 6.73 7.4 6.8 5.3Avg Hi Wgt New2 5.6 8.0 8.2 10.8 6.6 Hi Wgt New1* Front 6.9 10.5 7.412.2 7.6 Hi Wgt New1* Middle 5.3 8.97 9.0 9.2 6.3 Hi Wgt New1* Back 5.88.6 9.0 10.4 6.9 Avg Hi Wgt New1 6.0 9.4 8.5 10.6 6.9

TABLE 10 Permeability, CFM in BOTTOM region Position 1 2 3 4 5 Lo WgtONE-STEP Front 32.1 32.6 32.5 32.5 31.6 Lo Wgt ONE-STEP Middle 32.6 32.532.4 32.0 31.6 Lo Wgt ONE-STEP Back 31.5 31.5 32.3 32.4 33.0 Avg Lo WgtONE-STEP 32.1 32.2 32.4 32.3 32.1 Lo Wgt Seq Front 31.4 30.6 30.4 30.329.0 Lo Wgt Seq Middle 31.3 30.6 30.4 30.1 30.8 Lo Wgt Seq Back 31.230.7 30.7 30.3 30.0 Avg Lo Wgt Seq 31.3 30.6 30.5 30.2 29.9 Lo Wgt New2Front 26.6 27.2 26.3 25.7 24.2 Lo Wgt New2 Middle 26.1 26.9 26.5 25.424.5 Lo Wgt New2 Back 27.1 27.6 27.2 25.75 25 Avg Lo Wgt New2 26.6 27.226.6 25.6 24.6 Lo Wgt New1 Front 25.6 26.1 27.4 26.1 24.5 Lo Wgt New1Middle 25.3 26.05 27.2 25.7 24.8 Lo Wgt New1 Back 25.1 26.2 27.8 26.323.5 Avg Lo Wgt New1 25.3 26.1 27.4 26.0 24.2

TABLE 11 Permeability, CFM in TOP region Position: 1 2 3 4 5 Lo WgtONE-STEP Front 6.8 7.1 6.2 5.7 6.8 Lo Wgt ONE-STEP Middle 7.25 5.8 6.26.2 7.6 Lo Wgt ONE-STEP Back 8.2 6.9 10.9 7.4 7.5 Avg Lo Wgt ONE-STEP7.4 6.6 7.8 6.4 7.3 Lo Wgt Seq Front 7.0 6.0 6.1 5.3 7.1 Lo Wgt SeqMiddle 7.3 4.5 4.3 5.3 7.2 Lo Wgt Seq Back 8.5 6.6 6.4 8.2 7.9 Avg LoWgt Seq 7.6 5.7 5.6 6.3 7.4 Lo Wgt New2 Front 6.4 10.4 10.5 13.1 7.2 LoWgt New2 Middle 6.2 7.9 12.1 10.5 6.7 Lo Wgt New2 Back 7.38 7.6 13.4 8.57.7 Avg Lo Wgt New2 6.6 8.6 12.0 10.7 7.2 Lo Wgt New1 Front 12.8 17.314.8 18.2 16.5 Lo Wgt New1 Middle 7.5 13.4 14.5 7.9 6.4 Lo Wgt New1 Back9.4 12.9 13.3 6.7 9.6 Avg Lo Wgt New1 9.9 14.5 14.2 10.9 10.8

TABLE 12 Wgt, gms in BOTTOM region Position: 1 2 3 4 5 Hi Wgt ONE-STEPFront 0.68 0.71 0.70 0.70 0.69 Hi Wgt ONE-STEP Middle 0.67 0.68 0.710.69 0.68 Hi Wgt ONE-STEP Back 0.68 0.67 0.69 0.70 0.68 Avg Hi WgtONE-STEP 0.67 0.69 0.70 0.70 0.68 Hi Wgt Seq Front 0.66 0.68 0.67 0.690.68 Hi Wgt Seq Middle 0.68 0.67 0.68 0.67 0.70 Hi Wgt Seq Back 0.690.66 0.68 0.67 0.71 Avg Hi Wgt Seq 0.67 0.67 0.68 0.67 0.69 Hi Wgt New2Front 0.92 0.67 0.73 0.72 0.73 Hi Wgt New2 Middle 0.94 0.66 0.73 0.710.69 Hi Wgt New2 Back 0.94 0.65 0.74 0.72 0.73 Avg Hi Wgt New2 0.93 0.660.73 0.72 0.72 Hi Wgt New1* Front 0.96 0.69 0.70 0.71 0.83 Hi Wgt New1*Middle 0.92 0.70 0.72 0.73 0.81 Hi Wgt New1* Back 0.89 0.72 0.70 0.690.73 Avg Hi Wgt New1 0.92 0.70 0.71 0.71 0.79

TABLE 13 Wgt, gms in TOP region Position: 1 2 3 4 5 Hi Wgt ONE-STEPFront 4.17 3.58 3.99 3.88 4.53 Hi Wgt ONE-STEP Middle 3.56 3.68 5.964.10 3.57 Hi Wgt ONE-STEP Back 3.24 3.38 3.92 3.67 3.20 Avg Hi WgtONE-STEP 3.66 3.55 4.62 3.88 3.77 Hi Wgt Seq Front 3.98 3.74 4.87 4.184.61 Hi Wgt Seq Middle 3.50 3.85 5.54 4.58 3.59 Hi Wgt Seq Back 3.183.25 3.72 3.41 3.23 Avg Hi Wgt Seq 3.56 3.61 4.71 4.06 3.81 Hi Wgt New2Front 3.24 1.57 1.77 1.53 2.54 Hi Wgt New2 Middle 3.59 2.28 1.60 1.543.34 Hi Wgt New2 Back 2.98 2.65 1.71 1.65 2.98 Avg Hi Wgt New2 3.27 2.171.70 1.57 2.95 Hi Wgt New1* Front 2.64 1.25 1.66 1.19 2.12 Hi Wgt New1*Middle 2.94 1.8 1.45 1.38 2.66 Hi Wgt New1* Back 2.43 2.33 1.45 1.572.84 Avg Hi Wgt New1 2.67 1.80 1.52 1.38 2.54

TABLE 14 Wgt, gms in Top region Position: 1 2 3 4 5 Lo Wgt ONE-STEPFront 2.06 2.00 2.37 2.39 2.26 Lo Wgt ONE-STEP Middle 1.85 2.48 2.992.58 1.87 Lo Wgt ONE-STEP Back 1.76 1.94 1.92 2.21 1.86 Avg Lo WgtONE-STEP 1.89 2.14 2.43 2.39 2.00 Lo Wgt Seq Front 2.03 2.57 2.31 2.661.96 Lo Wgt Seq Middle 1.87 3.18 3.37 2.47 1.73 Lo Wgt Seq Back 1.651.99 2.22 1.88 1.69 Avg Lo Wgt Seq 1.85 2.59 2.63 2.34 1.79 Lo Wgt New2Front 2.02 1.12 1.01 0.88 1.67 Lo Wgt New2 Middle 1.92 1.60 0.90 1.111.86 Lo Wgt New2 Back 1.67 1.66 0.85 1.23 1.71 Avg Lo Wgt New2 1.87 1.460.92 1.08 1.75 Lo Wgt New1 Front 1.08 0.61 0.63 0.54 0.99 Lo Wgt New1Middle 1.57 0.96 0.66 1.10 1.56 Lo Wgt New1 Back 1.31 1.06 0.72 1.341.34 Avg Lo Wgt New1 1.32 0.88 0.67 0.99 1.30

TABLE 15 Wgt, gms in BOTTOM region Position: 1 2 3 4 5 Lo Wgt ONE-STEPFront 0.36 0.35 0.35 0.36 0.36 Lo Wgt ONE-STEP Middle 0.35 0.35 0.350.35 0.36 Lo Wgt ONE-STEP Back 0.35 0.35 0.36 0.36 0.36 Avg Lo WgtONE-STEP 0.35 0.35 0.35 0.35 0.36 Lo Wgt Seq Front 0.36 0.35 0.35 0.350.35 Lo Wgt Seq Middle 0.36 0.35 0.35 0.35 0.35 Lo Wgt Seq Back 0.350.35 0.35 0.35 0.35 Avg Lo Wgt Seq 0.35 0.35 0.35 0.35 0.35 Lo Wgt New2Front 0.46 0.35 0.35 0.35 0.41 Lo Wgt New2 Middle 0.45 0.36 0.35 0.360.39 Lo Wgt New2 Back 0.42 0.35 0.35 0.35 0.41 Avg Lo Wgt New2 0.44 0.350.35 0.35 0.40 Lo Wgt New1 Front 0.41 0.35 0.35 0.35 0.47 Lo Wgt New1Middle 0.42 0.35 0.35 0.35 0.46 Lo Wgt New1 Back 0.42 0.35 0.35 0.350.47 Avg Lo Wgt New1 0.42 0.35 0.35 0.35 0.47

TABLE 16 Wgt, gms in SIDE STRIP region SIDE STRIP Wgt, Position gms 1 23 4 5 6 7 8 9 10 11 12 13 14 15 16 Avg Lo Wgt ONE-STEP 0.3 0.4 0.3 0.40.3 0.8 1.3 0.9 1.4 1.5 1.6 2.1 1.9 1.7 1.1 0.9 Avg Lo Wgt Seq 0.3 0.40.4 0.4 0.3 1.0 1.2 1.3 1.4 1.8 2.3 1.7 1.3 1.1 1.5 1.2 Avg Lo Wgt New20.4 0.4 0.4 0.4 0.5 2.2 1.6 1.5 1.5 1.4 0.9 1.1 1.6 2.4 1.9 1.6 Avg LoWgt New1 0.5 0.3 0.3 0.4 0.5 1.8 2.4 1.7 1.1 0.7 0.7 0.8 1.2 1.9 2.0 1.7

TABLE 17 Maximum Plies in SIDE STRIP region of wrappings Position 1 2 34 5 6 7 8 9 10 11 12 13 14 15 16 Avg Lo Wgt ONE-STEP 2 2 2 2 2 12.0 13.715.7 15.7 16.7 16.0 19.5 26.0 29.5 12.0 8.7 Avg Lo Wgt Seq 2 2 2 2 210.7 12.3 21.0 17.0 18.7 41.7 16.0 16.7 13.7 16.7 16.0 Avg Lo Wgt New2 32 2 2 3 14.0 12.0 14.0 18.5 10.0 5.5 8.5 16.5 26.0 14.5 11.0 Avg Lo WgtNew1 3 2 2.5 2 3 11.5 23.0 12.0 12.5 6.0 4.5 5.5 17.5 28.0 16.5 12.5

TABLE 18 Wgt, gms in SIDE STRIP region Position 1 2 3 4 5 6 7 8 9 10 1112 13 14 15 16 Avg Hi Wgt ONE-STEP 0.7 0.7 0.7 0.7 0.7 2.2 2.7 2.7 3.03.2 3.1 3.1 2.9 3.1 2.7 2 Avg Hi Wgt Seq 0.7 0.7 0.7 0.7 0.7 2.5 2.8 3.52.9 3.1 2.9 3.0 2.9 2.9 2.7 2.7 Avg Hi Wgt New2 0.7 0.7 0.7 0.7 0.9 4.13.4 3.2 2.9 2.2 1.6 1.7 2.4 3.3 3.8 3.4 Avg Hi Wgt New1 0.7 0.7 0.7 0.71.0 3.9 4.6 3.3 1.6 1.3 1.1 1.2 2.0 4.3 3.9 2.8

TABLE 19 Maximum Plies in SIDE STRIP region of wrappings Position 1 2 34 5 6 7 8 9 10 11 12 13 14 15 16 Avg Hi Wgt ONE-STEP 2.0 2.0 2.0 2.0 2.011.7 11.3 11.0 10.7 9.7 14.0 10.0 15.3 7.7 14.0 12.7 Avg Hi Wgt Seq 2.02.0 2.7 2.3 2.0 11.3 12.7 24.3 12.0 12.0 13.0 13.0 14.0 15.0 13.7 14.3Avg Hi Wgt New2 2.5 2.0 1.5 2.0 3.0 18.0 9.0 9.0 11.5 10.0 5.0 9.0 10.016.0 13.5 11.5 Avg Hi Wgt New1 2.0 2.0 2.0 2.0 3.0 11.0 12.0 11.0 7.06.0 5.0 5.0 7.0 15.0 11.0 12.0

As can be seem from these Tables, the multi-panel sterilization assemblyof the present invention provides less than ten (10) stacked plies ofmaterial in the central portion of the Top region 402.

FIG. 26 shows the averaged values of the maximum number of plies (Plies)in 3-inch diameter specimens of all Hi Wgt wrappings taken from the 3×5array from the Bottom region versus their relative row position. Some ofthe invention's numbers of plies exceed 2 at the 1 and 5 positions dueto the presence of the reinforcement elements. The data is listed inTable 5. The absence of consistently counting two plies for the New1 andNew2 samples in positions 2, 3, and 4 is attributed to the tackingtogether the barrier panels by adhesive that was optionally used intheir construction; the consistency among the Wgt values shown in FIG.35 and listed in Table 12 confirm the presence of two barrier panels forNew1 and New2 samples.

FIG. 27 shows the Plies averages among the respective Front, Middle andBack row averaged values of FIG. 26 for each Hi Wgt sample. Thispresents the Avg data for the samples that are listed in Table 5.

FIG. 28 shows the averaged values of the Plies in 3-inch diameterspecimens taken from the 3×5 array from the Top region of Hi Wgtwrappings versus their relative row position. All but the invention'sPlies in the 1 and 5 positions are less than the corresponding averagedvalues for the envelope folded wrappings. The data is listed in Table 6.

FIG. 29 shows the Plies averages among the respective Front, Middle andBack row averaged values of FIG. 28 for each Hi Wgt sample. Thispresents the Avg data for the samples that are listed in Table 6.Comparing FIG. 29 to FIG. 28 visually shows that representing the 3×5array's averaged values for Plies as averages among the rows relative totheir position retains the validity of the distinctions of the inventionfrom the conventional envelope fold for Hi Wgt wrappings. This Figure,like FIG. 28, clearly shows that the Plies for the invention in thecenter of the Top region consistently average less than 10 stacked plieswhile the Plies for the envelope fold are greater.

FIG. 30 shows the Plies averages among the respective Front, Middle andBack row averaged values for each Lo Wgt sample for the Top and Bottomregions. This data is presented in Table 7. This Figure, like FIG. 29for the Hi Wgt samples, clearly shows that the Plies in the center ofthe Top region for the invention also consistently average less than 10stacked plies while the Plies in the Top region for the envelope foldare greater.

FIGS. 31 and 33 show the general uniformity of Permeability through theBottom regions for Hi Wgt and Lo Wgt samples and the differences areinsignificant and are attributed to the presence (or absence) ofreinforcement panels for the New1 and New2 samples, corresponding Wgtvariations as respectively shown in FIGS. 35 and 38, and the inherentsingle ply permeability and basis weight variability as evidenced byTable 2.

FIGS. 32 and 34 show greater permeability in the central area of the Topregion for the New1 and New2 samples compared to the other samples. Thisdifference is attributed to the fewer Plies for New1 and New2 versus theother samples as respectively shown in FIGS. 29 and 30 and theircorresponding Wgt values of FIGS. 37 and 36.

FIGS. 39-42 indicate the relationship between Plies and Wgtcontributions and a greater concentration of Plies for New1 and New2samples in the 5 to 9 positions and the 12 to 15 positions unlike theother samples.

Example 4

Testing of multi-panel sterilization assemblies were conducted using theExposure Chamber Method outline by Dunkelberg H., Schmelz, U.,Determination of the Efficacy of Sterile Barrier Systems AgainstMicrobial Challenges During Transport and Storage, Infect. Control Hosp.Epidemiol. 2009; 30:179-183. The aim of this testing was to determinethe microbial barrier effectiveness of the multi-panel sterilizationassemblies in comparison to the current sterilization wrap product. Eachprototype was tested 10 times. One set of prototypes were prepared inwhich the barrier panel was constructed of two plies of KC200 material.Another set of prototypes was constructed of two plies of KC400material. These prototypes had dimensions as generally set forth inExample 2 and were used for the small tray size noted below.Proportionally larger prototypes were used for the large tray size notedbelow.

The size of the trays used was 250 mm×240×50 mm (small tray size) and480 mm×24 mm×50 mm (large tray size). The trays were loaded withthermo-resistant dishes (140 mm×20 mm) filled with nutrient agar (CASOagar, Oxoid) prior to sterilization. For the large trays 2 dishes withculture medium were used.

Control samples were wrapped using KC 200 and K-C 400 KimGuard®One-Step® wrap using the conventional envelope fold technique. Doublepaper sheet packaging that are conventionally used as sterilization wrapwere also used as control. Two wrapped trays of each prototype wereprepared for 1 test run. In total 5 runs were done. The wrapped trayswere positioned in shelves and then sterilized at 118° C. for 25 minutes(steam sterilization).

Using the exposure chamber method, the wraps were exposed to about 24periodic atmospheric pressure changes of 70 hPa after sterilization andto an airborne bacteria challenge of Micrococcus luteus of about 5×106to 5×107 cfu (colony forming units) per m³. The microbial aerosol in theexposure chamber was produced by a nebulizer. As specified by themanufacturer, the median diameter of particles was 3.9 μm. Theatmospheric pressure changes, the temperatures and the humidity weremonitored continuously by an electronic data logger. Using an airsampler (impinger), samples of air were taken continuously by a vacuumpump in order to determine the mean airborne microbial concentration inthe chamber. 5 uncovered settle plates with nutrient agar were placed ascontrols in the chamber to detect surface microbial load. After theexposure, the test items were incubated at 37° for 72 hours and thenexamined for colony growth. 5 runs were needed to test each prototype 10times. The effectiveness of the microbial barrier was expressed as thelogarithmic reduction value (LRV) and percent reduction. The testedprototypes and KimGuard® wrap controls showed no growth on the disheswith nutrient agar after incubation. The calculated LRV's of themicrobial barrier of the examined concepts for terminally sterilizedproducts were >6.09, that corresponds to a microbial reduction of>99.99992%.

Using the exposure chamber method, the different tested prototypes ofwrapping material and KimGuard® wrap controls showed no bacterialrecontamination after sterilization and exposure to airborne bacteria.The barrier efficiency was >99.99992%. 6 out of 10 tested double papersheet packaging showed recontamination. A LRV of 3.90 and a microbialreduction of 99.987% were obtained as results for the paper sheetpackaging.

Thus, exemplary embodiments of the invention are presented herein;however, the invention may be embodied in a variety of alternativeforms, as will be apparent to those skilled in the art. To facilitateunderstanding of the invention, and provide a basis for the claims,various figures are included in the description. The figures are notdrawn to scale and related elements may be omitted so as to emphasizethe novel features of the invention. Structural and functional detailsdepicted in the figures are provided for the purpose of teaching thepractice of the invention to those skilled in the art and are notintended to be considered limitations. Directional terms such as left,right, front or rear are provided to assist in the understanding of theinvention and are not intended to be considered as limitations.

While particular embodiments of the present invention have beendescribed herein; it will be apparent to those skilled in the art thatalterations and modifications may be made to the described embodimentswithout departing from the scope of the appended claims.

1-17. (canceled)
 18. A disposable flexible multi-panel sterilizationassembly comprising: a barrier panel comprising a sheet of barriermaterial, the sheet defining at least one panel edge, the barrier panelconfigured to be folded around content to be sterilized to form apackage; barrier panel attachment means located on a portion of thebarrier panel in close proximity to one or more panel edges or extendingfrom one or more panel edges, the barrier panel attachment means beingjoined to the barrier panel in order to secure one or more edges of thebarrier panel in a folded configuration around content to be sterilized;a fold protection panel extending from the barrier panel, the foldprotection panel including: a proximal end generally adjacent thebarrier panel, a distal end generally opposite the proximal end; andwherein the distal end of the fold protection panel covers the one ormore panel edges of the barrier panel including the barrier panelattachment means after the barrier panel is in the folded configuration.19. A disposable flexible multi-panel sterilization assembly comprising:a barrier panel comprising a sheet of barrier material, the sheetdefining at least one panel edge, the barrier panel configured to befolded around content to be sterilized to form a package; barrier panelattachment means located on a portion of the barrier panel for securingone or more panel edges of the barrier panel in a folded configurationaround content to be sterilized, the barrier panel fastening meansconfigured to secure the one or more panel edges in a foldedconfiguration; a fold protection panel extending from the barrier panel,the fold protection panel including: a proximal end generally adjacentthe barrier panel, a distal end generally opposite the proximal end; andwherein the distal end of the fold protection panel covers the one ormore panel edges of the barrier panel after the barrier panel is in thefolded configuration and wherein less than ten (10) stacked plies ofmaterial are present as a result of folding of the sterilizationassembly around an article.
 20. The sterilization assembly of claim 19,wherein less than five (5) stacked plies of material are present as aresult of folding of the sterilization assembly around an article.
 21. Adisposable flexible multi-panel sterilization assembly comprising: abarrier panel comprising a permeable sheet material having barrierproperties, the barrier panel including: a first surface and a secondopposing surface, a first end generally defining a pre-determined foldline, a second end opposite the first end, a first edge that isgenerally perpendicular to the pre-determined fold line, a second edgethat is generally opposite the pre-determined fold line, and a thirdedge that is generally perpendicular to the pre-determined fold line,the barrier panel having a having a width that is the distance from thefirst edge to the third edge and a length that is the distance from thefirst end to the second end, the barrier panel having a midpoint alongthe length and extending between the first edge and the third edge togenerally delineate the barrier panel into a content receiving regionextending from the pre-determined fold line to the midpoint and acontent covering region extending from the midpoint to the second edge;a panel attachment means between the pre-determined fold line and themidpoint of the barrier panel and at or near the first edge or the thirdedge; the panel attachment means being joined to the barrier panel at apre-determined position to identify the barrier panel's contentreceiving region and further to join the barrier panel's first edge andthird edge to each other or to a portion of the content covering regionafter the barrier panel has been folded at or near its midpoint suchthat its second end is brought near its first end; and a fold protectionpanel in juxtaposed communication with the barrier panel, the foldprotection panel comprising a permeable sheet material, the foldprotection panel including: a proximal end generally adjacent thepre-determined fold line, a distal end generally opposite the proximalend; and at least a first edge and a second edge extending from theproximal end to the distal end, the fold protection panel having a widththat is the distance from the first edge to the second edge and a lengththat is the distance from the proximal end to the distal end, such that,after the barrier panel has been folded at or near the barrier panel'smidpoint so the barrier panel's second end is brought near its first endand its first and third edges are joined to each other or to its contentcovering region to form a package, the fold protection panel isconfigured to fold at or near the pre-determined fold line to cover atleast the first edge and the third edge of the folded barrier panel,wherein the permeable sheet material having barrier properties comprisesmultiple layers or plies of a nonwoven laminate material and thepermeability of the barrier panel is from about 10 cubic feet per minuteto about 30 cubic feet per minute when determined generally inaccordance with ISO 9237:1995.
 22. The sterilization assembly of claim21, wherein the barrier panel has a fourth edge.
 23. The sterilizationassembly of claim 22, wherein the barrier panel includes a fifth edge.24. The sterilization assembly of claim 21, wherein the panel attachmentmeans is at or near both the first edge and the third edge of thebarrier panel.
 25. The sterilization assembly of claim 24, wherein thepanel attachment means is located at and extends from the first edge andthe third edge of the barrier panel.
 26. The sterilization assembly ofclaim 21, wherein the panel attachment means is selected from adhesivetape, double-sided adhesive tape, cohesive materials, hook and loopfastening systems, mechanical fastening systems, snaps, clips, magnets,catches, slots and tabs, and combinations thereof.
 27. The sterilizationassembly of claim 21, wherein the nonwoven laminate material comprisinga layer of spunbonded filaments, a layer of meltblown fibers, and alayer of spunbonded filaments.
 28. The sterilization assembly of claim21, wherein the sterilization assembly further includes at least onepull tab extending from the second end of the barrier panel.
 29. Thesterilization assembly of claim 26, wherein the panel attachment meansfurther includes a length of fabric having an end or portion joined tothe barrier panel.
 30. The sterilization assembly of claim 21, whereinthe fold protection panel has at least a third edge located at or alongits distal end.
 31. The sterilization assembly of claim 21, wherein thefold protection panel has barrier properties.
 32. The sterilizationassembly of claim 21, wherein the sterilization assembly furthercomprises discrete reinforcement elements in the content receivingregion that define an area for receiving content to be sterilized. 33.The sterilization assembly of claim 32, wherein the reinforcementelements comprise a layer of material are selected from fibrous webs,impermeable films, permeable or porous films, apertured films, foams,foils and combinations thereof.
 34. The sterilization assembly of claim21, wherein the sterilization assembly further comprises indicia orinstructions on the sterilization assembly to inform the proper foldingof the assembly into a package.
 35. The sterilization assembly of claim21, wherein the surface area of the content receiving region is betweenabout 25 percent to about 49 percent of the total surface area of thebarrier panel.
 36. A disposable flexible multi-panel sterilizationassembly comprising: a barrier panel comprising a permeable nonwovensheet material having barrier properties, the barrier panel including: afirst surface and a second opposing surface, a first end generallydefining a pre-determined fold line, a second end opposite the firstend, a first edge that is generally perpendicular to the pre-determinedfold line, a second edge that is generally parallel to thepre-determined fold line, and a third edge that is generallyperpendicular to the pre-determined fold line, and a fourth edge locatedbetween the second edge and the third edge; the barrier panel having awidth that is the distance from the first edge to the third edge and anapex or vertex defined by the second edge and fourth edge; a length thatis the distance from the first end to the second end, the barrier panelhaving a midpoint along the length and extending between the first edgeand the third edge to generally delineate the barrier panel into acontent receiving region extending from the pre-determined fold line tothe midpoint and a content covering region extending from the midpointto the second edge; at least one pull tab extending from the second endof the barrier panel; a panel attachment means between thepre-determined fold line and the midpoint of the barrier panel and at ornear the first edge or the third edge; the panel attachment means beingjoined to the barrier panel at a pre-determined position to identify thebarrier panel's content receiving region and further to join the barrierpanel's first edge and third edge to each other or to a portion of thecontent covering region after the barrier panel has been folded at ornear its midpoint such that its second edge is brought near its firstend; and a fold protection panel in juxtaposed communication with thebarrier panel, the fold protection panel comprising a permeable nonwovensheet material, the fold protection panel including: a proximal endgenerally adjacent the pre-determined fold line, a distal end generallyopposite the proximal end; and at least a first edge and a second edgeextending from the proximal end to the distal end, the fold protectionpanel having a width that is the distance from the first edge to thesecond edge and a length that is the distance from the proximal end tothe distal end, such that, after the barrier panel has been folded at ornear its midpoint so its second end is brought near its first end andits first and third edges are joined to each other or to its contentcovering region to form a package, the fold protection panel isconfigured to fold at or near the pre-determined fold line to cover atleast the first edge and the third edge of the folded barrier panel.